21431996 has 6 divisors (see below), whose sum is σ = 37506000. Its totient is φ = 10715996.

The previous prime is 21431983. The next prime is 21432013. The reversal of 21431996 is 69913412.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2678996 + ... + 2679003.

It is an arithmetic number, because the mean of its divisors is an integer number (6251000).

Almost surely, 2^21431996 is an apocalyptic number.

It is an amenable number.

21431996 is a deficient number, since it is larger than the sum of its proper divisors (16074004).

21431996 is a wasteful number, since it uses less digits than its factorization.

21431996 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5358003 (or 5358001 counting only the distinct ones).

The product of its digits is 11664, while the sum is 35.

The square root of 21431996 is about 4629.4703800759. The cubic root of 21431996 is about 277.7714077591.

The spelling of 21431996 in words is "twenty-one million, four hundred thirty-one thousand, nine hundred ninety-six".