215604001 has 18 divisors (see below), whose sum is σ = 238083090. Its totient is φ = 195202656.

The previous prime is 215603959. The next prime is 215604023. The reversal of 215604001 is 100406512.

It can be written as a sum of positive squares in only one way, i.e., 139216401 + 76387600 = 11799^2 + 8740^2 .

It is not a de Polignac number, because 215604001 - 2¹⁵ = 215571233 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 215604001.

It is not an unprimeable number, because it can be changed into a prime (215604031) 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, 190405 + ... + 191533.

Almost surely, 2^215604001 is an apocalyptic number.

It is an amenable number.

215604001 is a deficient number, since it is larger than the sum of its proper divisors (22479089).

215604001 is a wasteful number, since it uses less digits than its factorization.

215604001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1213 (or 1171 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 215604001 is about 14683.4601167436. The cubic root of 215604001 is about 599.6331099578.

The spelling of 215604001 in words is "two hundred fifteen million, six hundred four thousand, one".