21604660636275 has 36 divisors (see below), whose sum is σ = 38696757915400. Its totient is φ = 11522363529600.

The previous prime is 21604660636261. The next prime is 21604660636333. The reversal of 21604660636275 is 57263606640612.

21604660636275 is a `hidden beast` number, since 2 + 1 + 6 + 0 + 4 + 6 + 6 + 0 + 6 + 3 + 627 + 5 = 666.

It is not a de Polignac number, because 21604660636275 - 2²⁸ = 21604392200819 is a prime.

It is a super-2 number, since 2×21604660636275² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 23216151 + ... + 24128799.

Almost surely, 2^{21604660636275} is an apocalyptic number.

21604660636275 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21604660636275 is a deficient number, since it is larger than the sum of its proper divisors (17092097279125).

21604660636275 is a wasteful number, since it uses less digits than its factorization.

21604660636275 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1017876 (or 1017868 counting only the distinct ones).

The product of its (nonzero) digits is 13063680, while the sum is 54.

The spelling of 21604660636275 in words is "twenty-one trillion, six hundred four billion, six hundred sixty million, six hundred thirty-six thousand, two hundred seventy-five".