A153427 -id:A153427 - cp's OEIS frontend

A153428 Numbers n such that phi(n) = p^3, where p is product of digits of n.

1, 14611, 141152, 2831112, 113216152, 419521121, 5342121213, 7112216125, 11191442171, 11371542112, 12192256111, 12327134121, 12432712113, 13161313512, 14132133215, 113335111416, 127131142512, 133412214117, 196112145112, 311721152134, 312118111536, 312127213125, 322631161151, 411111553831, 432122133312

Offset: 1

Farideh Firoozbakht, Jan 02 2009

			phi(113216152) = (1*1*3*2*1*6*1*5*2)^3, so 113216152 is in the sequence.

Hiroaki Yamanouchi, Table of n, a(n) for n = 1..404 (terms a(1)-a(48) from _Max Alekseyev_)

Cf. A068572, A153427.

Do[If[Apply[Times,IntegerDigits[n]]^3==EulerPhi[n],Print[n]],{n,300000000}]

a(6)-a(18) from Donovan Johnson, Nov 01 2010
a(19)-a(22) from Donovan Johnson, Aug 15 2013
a(23)-a(48) from Max Alekseyev, Aug 18 2013

A171267 Primes p such that p^s ends with p, where s is sum of the digits of p.

Original entry on oeis.org

5, 29, 193, 557, 751, 3307, 4999, 7499, 16693, 20807, 31249, 59999, 60443, 79193, 812501, 918751, 5422943, 46295807, 55781249, 74218751, 78281249, 89218751, 89999999, 282922943, 316295807, 674218751, 1583704193, 3824218751, 3958704193, 4092077057, 6342077057, 8324218751, 31666295807, 47779577057, 64478795807, 66666295807, 75000000001

Offset: 1

Farideh Firoozbakht, Apr 28 2010

			1583704193^(1+5+8+3+7+0+4+1+9+3)=1583704193 (mod 10^10) so 1583704193 is
in the sequence.
It is interesting that each of the four numbers 751^(7+5+1), 751^(7*5*1),
751^pi(751) and 751^prime(751) ends with 751.

Max Alekseyev, Table of n, a(n) for n = 1..107

Cf. A171268, A153427, A153428.

Do[n=Prime[m];a=IntegerDigits[n];If[PowerMod[n,Apply[Plus,a],10^Length[a]]
==n,Print[n]],{m,100000000}]

Terms a(28) onward from Max Alekseyev, Aug 18 2013

cp's OEIS Frontend

A153428 Numbers n such that phi(n) = p^3, where p is product of digits of n.

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