21255392 has 24 divisors (see below), whose sum is σ = 42007896. Its totient is φ = 10586752.

The previous prime is 21255383. The next prime is 21255401. The reversal of 21255392 is 29355212.

It is an interprime number because it is at equal distance from previous prime (21255383) and next prime (21255401).

It is a congruent number.

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, 8243 + ... + 10509.

It is an arithmetic number, because the mean of its divisors is an integer number (1750329).

Almost surely, 2^21255392 is an apocalyptic number.

It is an amenable number.

21255392 is a deficient number, since it is larger than the sum of its proper divisors (20752504).

21255392 is a wasteful number, since it uses less digits than its factorization.

21255392 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2570 (or 2562 counting only the distinct ones).

The product of its digits is 5400, while the sum is 29.

The square root of 21255392 is about 4610.3570360656. The cubic root of 21255392 is about 277.0063381799.

The spelling of 21255392 in words is "twenty-one million, two hundred fifty-five thousand, three hundred ninety-two".