165556800 has 126 divisors (see below), whose sum is σ = 588479138. Its totient is φ = 44144640.

The previous prime is 165556793. The next prime is 165556801. The reversal of 165556800 is 8655561.

It can be written as a sum of positive squares in 3 ways, for example, as 14561856 + 150994944 = 3816^2 + 12288^2 .

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 (165556801) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 8652 + ... + 20148.

Almost surely, 2^165556800 is an apocalyptic number.

165556800 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 165556800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (294239569).

165556800 is an abundant number, since it is smaller than the sum of its proper divisors (422922338).

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

165556800 is a wasteful number, since it uses less digits than its factorization.

165556800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11525 (or 11507 counting only the distinct ones).

The product of its (nonzero) digits is 36000, while the sum is 36.

The square root of 165556800 is about 12866.8877355793. The cubic root of 165556800 is about 549.0969201915.

The spelling of 165556800 in words is "one hundred sixty-five million, five hundred fifty-six thousand, eight hundred".