165904402 has 4 divisors (see below), whose sum is σ = 248856606. Its totient is φ = 82952200.

The previous prime is 165904393. The next prime is 165904421. The reversal of 165904402 is 204409561.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 162027441 + 3876961 = 12729^2 + 1969^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41476099 + ... + 41476102.

Almost surely, 2^165904402 is an apocalyptic number.

165904402 is a deficient number, since it is larger than the sum of its proper divisors (82952204).

165904402 is an equidigital number, since it uses as much as digits as its factorization.

165904402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82952203.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 165904402 is about 12880.3882705453. The cubic root of 165904402 is about 549.4809450138.

The spelling of 165904402 in words is "one hundred sixty-five million, nine hundred four thousand, four hundred two".