156805920 has 72 divisors (see below), whose sum is σ = 535105116. Its totient is φ = 41814528.

The previous prime is 156805867. The next prime is 156805921. The reversal of 156805920 is 29508651.

It is a happy number.

156805920 is a `hidden beast` number, since 1 + 5 + 68 + 0 + 592 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 155451024 + 1354896 = 12468^2 + 1164^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (156805921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 53007 + ... + 55886.

Almost surely, 2^156805920 is an apocalyptic number.

156805920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

156805920 is an abundant number, since it is smaller than the sum of its proper divisors (378299196).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

156805920 is a wasteful number, since it uses less digits than its factorization.

156805920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108914 (or 108903 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 36.

The square root of 156805920 is about 12522.2170560967. The cubic root of 156805920 is about 539.2466862222.

The spelling of 156805920 in words is "one hundred fifty-six million, eight hundred five thousand, nine hundred twenty".