21928964 has 12 divisors (see below), whose sum is σ = 40395600. Its totient is φ = 10387368.

The previous prime is 21928957. The next prime is 21928969. The reversal of 21928964 is 46982912.

It is a super-2 number, since 2×21928964² = 961758924226592, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21928969) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 144194 + ... + 144345.

It is an arithmetic number, because the mean of its divisors is an integer number (3366300).

Almost surely, 2^21928964 is an apocalyptic number.

It is an amenable number.

21928964 is a deficient number, since it is larger than the sum of its proper divisors (18466636).

21928964 is a wasteful number, since it uses less digits than its factorization.

21928964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 288562 (or 288560 counting only the distinct ones).

The product of its digits is 62208, while the sum is 41.

The square root of 21928964 is about 4682.8371741926. The cubic root of 21928964 is about 279.9020235436.

The spelling of 21928964 in words is "twenty-one million, nine hundred twenty-eight thousand, nine hundred sixty-four".