165220651207171 has 16 divisors (see below), whose sum is σ = 188898161400000. Its totient is φ = 141561783525888.

The previous prime is 165220651207127. The next prime is 165220651207201. The reversal of 165220651207171 is 171702156022561.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 165220651207171 - 2³³ = 165212061272579 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165220651202171) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1129648455 + ... + 1129794703.

It is an arithmetic number, because the mean of its divisors is an integer number (11806135087500).

Almost surely, 2^{165220651207171} is an apocalyptic number.

165220651207171 is a deficient number, since it is larger than the sum of its proper divisors (23677510192829).

165220651207171 is a wasteful number, since it uses less digits than its factorization.

165220651207171 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208878.

The product of its (nonzero) digits is 352800, while the sum is 46.

The spelling of 165220651207171 in words is "one hundred sixty-five trillion, two hundred twenty billion, six hundred fifty-one million, two hundred seven thousand, one hundred seventy-one".