21292672 has 16 divisors (see below), whose sum is σ = 42419250. Its totient is φ = 10646272.

The previous prime is 21292669. The next prime is 21292681. The reversal of 21292672 is 27629212.

It can be written as a sum of positive squares in only one way, i.e., 19149376 + 2143296 = 4376^2 + 1464^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83047 + ... + 83302.

Almost surely, 2^21292672 is an apocalyptic number.

It is an amenable number.

21292672 is a deficient number, since it is larger than the sum of its proper divisors (21126578).

21292672 is an equidigital number, since it uses as much as digits as its factorization.

21292672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166363 (or 166351 counting only the distinct ones).

The product of its digits is 6048, while the sum is 31.

The square root of 21292672 is about 4614.3983356446. The cubic root of 21292672 is about 277.1681914600.

The spelling of 21292672 in words is "twenty-one million, two hundred ninety-two thousand, six hundred seventy-two".