21576964 has 12 divisors (see below), whose sum is σ = 37911888. Its totient is φ = 10745000.

The previous prime is 21576959. The next prime is 21576979. The reversal of 21576964 is 46967512.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9742 + ... + 11749.

It is an arithmetic number, because the mean of its divisors is an integer number (3159324).

Almost surely, 2^21576964 is an apocalyptic number.

It is an amenable number.

21576964 is a deficient number, since it is larger than the sum of its proper divisors (16334924).

21576964 is a wasteful number, since it uses less digits than its factorization.

21576964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21746 (or 21744 counting only the distinct ones).

The product of its digits is 90720, while the sum is 40.

The square root of 21576964 is about 4645.1010753266. The cubic root of 21576964 is about 278.3962914301.

The spelling of 21576964 in words is "twenty-one million, five hundred seventy-six thousand, nine hundred sixty-four".