165558400 has 192 divisors, whose sum is σ = 493272000. Its totient is φ = 53637120.

The previous prime is 165558397. The next prime is 165558431. The reversal of 165558400 is 4855561.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 425406 + ... + 425794.

It is an arithmetic number, because the mean of its divisors is an integer number (2569125).

Almost surely, 2^165558400 is an apocalyptic number.

165558400 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 165558400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (246636000).

165558400 is an abundant number, since it is smaller than the sum of its proper divisors (327713600).

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

165558400 is a wasteful number, since it uses less digits than its factorization.

165558400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 439 (or 422 counting only the distinct ones).

The product of its (nonzero) digits is 24000, while the sum is 34.

The square root of 165558400 is about 12866.9499105266. The cubic root of 165558400 is about 549.0986890754.

The spelling of 165558400 in words is "one hundred sixty-five million, five hundred fifty-eight thousand, four hundred".