21684752 has 10 divisors (see below), whose sum is σ = 42014238. Its totient is φ = 10842368.

The previous prime is 21684739. The next prime is 21684763. The reversal of 21684752 is 25748612.

It can be written as a sum of positive squares in only one way, i.e., 20394256 + 1290496 = 4516^2 + 1136^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 677633 + ... + 677664.

Almost surely, 2^21684752 is an apocalyptic number.

It is an amenable number.

21684752 is a deficient number, since it is larger than the sum of its proper divisors (20329486).

21684752 is a wasteful number, since it uses less digits than its factorization.

21684752 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1355305 (or 1355299 counting only the distinct ones).

The product of its digits is 26880, while the sum is 35.

The square root of 21684752 is about 4656.6889524640. The cubic root of 21684752 is about 278.8590990428.

The spelling of 21684752 in words is "twenty-one million, six hundred eighty-four thousand, seven hundred fifty-two".