165601324800 has 2160 divisors, whose sum is σ = 728675861760. Its totient is φ = 36787322880.

The previous prime is 165601324799. The next prime is 165601324849. The reversal of 165601324800 is 8423106561.

It is a happy number.

165601324800 is a `hidden beast` number, since 1 + 6 + 5 + 601 + 3 + 2 + 48 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (2160).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 3851193579 + ... + 3851193621.

It is an arithmetic number, because the mean of its divisors is an integer number (337349936).

Almost surely, 2^165601324800 is an apocalyptic number.

165601324800 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 165601324800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (364337930880).

165601324800 is an abundant number, since it is smaller than the sum of its proper divisors (563074536960).

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

165601324800 is a wasteful number, since it uses less digits than its factorization.

165601324800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140 (or 112 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The spelling of 165601324800 in words is "one hundred sixty-five billion, six hundred one million, three hundred twenty-four thousand, eight hundred".