21172233465 has 32 divisors (see below), whose sum is σ = 37663862400. Its totient is φ = 11284557120.

The previous prime is 21172233443. The next prime is 21172233479. The reversal of 21172233465 is 56433227112.

21172233465 is a `hidden beast` number, since 2 + 1 + 172 + 23 + 3 + 465 = 666.

It is not a de Polignac number, because 21172233465 - 2⁷ = 21172233337 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 162171 + ... + 261999.

It is an arithmetic number, because the mean of its divisors is an integer number (1176995700).

Almost surely, 2^21172233465 is an apocalyptic number.

It is an amenable number.

21172233465 is a deficient number, since it is larger than the sum of its proper divisors (16491628935).

21172233465 is a wasteful number, since it uses less digits than its factorization.

21172233465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101414 (or 101408 counting only the distinct ones).

The product of its digits is 60480, while the sum is 36.

The spelling of 21172233465 in words is "twenty-one billion, one hundred seventy-two million, two hundred thirty-three thousand, four hundred sixty-five".