165256604665 has 128 divisors (see below), whose sum is σ = 234056908800. Its totient is φ = 111168184320.

The previous prime is 165256604657. The next prime is 165256604701. The reversal of 165256604665 is 566406652561.

It is not a de Polignac number, because 165256604665 - 2³ = 165256604657 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 376438516 + ... + 376438954.

It is an arithmetic number, because the mean of its divisors is an integer number (1828569600).

Almost surely, 2^165256604665 is an apocalyptic number.

It is an amenable number.

165256604665 is a deficient number, since it is larger than the sum of its proper divisors (68800304135).

165256604665 is a wasteful number, since it uses less digits than its factorization.

165256604665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 687.

The product of its (nonzero) digits is 7776000, while the sum is 52.

The spelling of 165256604665 in words is "one hundred sixty-five billion, two hundred fifty-six million, six hundred four thousand, six hundred sixty-five".