155981856 has 24 divisors (see below), whose sum is σ = 409452624. Its totient is φ = 51993920.

The previous prime is 155981843. The next prime is 155981857. The reversal of 155981856 is 658189551.

It is a tau number, because it is divible by the number of its divisors (24).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is not an unprimeable number, because it can be changed into a prime (155981857) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 812310 + ... + 812501.

It is an arithmetic number, because the mean of its divisors is an integer number (17060526).

Almost surely, 2^155981856 is an apocalyptic number.

155981856 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

155981856 is an abundant number, since it is smaller than the sum of its proper divisors (253470768).

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

155981856 is a wasteful number, since it uses less digits than its factorization.

155981856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1624824 (or 1624816 counting only the distinct ones).

The product of its digits is 432000, while the sum is 48.

The square root of 155981856 is about 12489.2696343701. The cubic root of 155981856 is about 538.3003900983.

The spelling of 155981856 in words is "one hundred fifty-five million, nine hundred eighty-one thousand, eight hundred fifty-six".