165978879 has 16 divisors (see below), whose sum is σ = 251921664. Its totient is φ = 96219200.

The previous prime is 165978863. The next prime is 165978893. The reversal of 165978879 is 978879561.

It is not a de Polignac number, because 165978879 - 2⁴ = 165978863 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165970879) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 108582 + ... + 110099.

It is an arithmetic number, because the mean of its divisors is an integer number (15745104).

Almost surely, 2^165978879 is an apocalyptic number.

165978879 is a deficient number, since it is larger than the sum of its proper divisors (85942785).

165978879 is a wasteful number, since it uses less digits than its factorization.

165978879 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218718.

The product of its digits is 7620480, while the sum is 60.

The square root of 165978879 is about 12883.2790468886. The cubic root of 165978879 is about 549.5631561539.

The spelling of 165978879 in words is "one hundred sixty-five million, nine hundred seventy-eight thousand, eight hundred seventy-nine".