155961806400 has 315 divisors, whose sum is σ = 573799431139. Its totient is φ = 41551902720.

The previous prime is 155961806381. The next prime is 155961806411. The reversal of 155961806400 is 4608169551.

The square root of 155961806400 is 394920.

It is a perfect power (a square), and thus also a powerful number.

155961806400 is a `hidden beast` number, since 1 + 5 + 596 + 18 + 0 + 6 + 40 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 19853937216 + 136107869184 = 140904^2 + 368928^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Duffinian number.

It is an unprimeable number.

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 44 ways as a sum of consecutive naturals, for example, 142170652 + ... + 142171748.

Almost surely, 2^155961806400 is an apocalyptic number.

155961806400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

155961806400 is the 394920-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 155961806400

155961806400 is an abundant number, since it is smaller than the sum of its proper divisors (417837624739).

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

155961806400 is an frugal number, since it uses more digits than its factorization.

155961806400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2228 (or 1107 counting only the distinct ones).

The product of its (nonzero) digits is 259200, while the sum is 45.

It can be divided in two parts, 155961 and 806400, that added together give a square (962361 = 981²).

The spelling of 155961806400 in words is "one hundred fifty-five billion, nine hundred sixty-one million, eight hundred six thousand, four hundred".