165800 has 24 divisors (see below), whose sum is σ = 385950. Its totient is φ = 66240.

The previous prime is 165799. The next prime is 165811. The reversal of 165800 is 8561.

It can be written as a sum of positive squares in 3 ways, for example, as 128164 + 37636 = 358^2 + 194^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a plaindrome in base 14.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 215 + ... + 614.

2¹⁶⁵⁸⁰⁰ is an apocalyptic number.

165800 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

165800 is an abundant number, since it is smaller than the sum of its proper divisors (220150).

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

165800 is a wasteful number, since it uses less digits than its factorization.

165800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 845 (or 836 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 165800 is about 407.1854614300. The cubic root of 165800 is about 54.9365659852.

The spelling of 165800 in words is "one hundred sixty-five thousand, eight hundred".