21831244 has 6 divisors (see below), whose sum is σ = 38204684. Its totient is φ = 10915620.

The previous prime is 21831217. The next prime is 21831253. The reversal of 21831244 is 44213812.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2728902 + ... + 2728909.

Almost surely, 2^21831244 is an apocalyptic number.

It is an amenable number.

21831244 is a deficient number, since it is larger than the sum of its proper divisors (16373440).

21831244 is a wasteful number, since it uses less digits than its factorization.

21831244 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5457815 (or 5457813 counting only the distinct ones).

The product of its digits is 1536, while the sum is 25.

The square root of 21831244 is about 4672.3916787872. The cubic root of 21831244 is about 279.4856373221.

The spelling of 21831244 in words is "twenty-one million, eight hundred thirty-one thousand, two hundred forty-four".