21317732 has 12 divisors (see below), whose sum is σ = 37341696. Its totient is φ = 10648680.

The previous prime is 21317729. The next prime is 21317749. The reversal of 21317732 is 23771312.

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, 4073 + ... + 7695.

It is an arithmetic number, because the mean of its divisors is an integer number (3111808).

Almost surely, 2^21317732 is an apocalyptic number.

It is an amenable number.

21317732 is a deficient number, since it is larger than the sum of its proper divisors (16023964).

21317732 is a wasteful number, since it uses less digits than its factorization.

21317732 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5098 (or 5096 counting only the distinct ones).

The product of its digits is 1764, while the sum is 26.

The square root of 21317732 is about 4617.1129507518. The cubic root of 21317732 is about 277.2768847503.

The spelling of 21317732 in words is "twenty-one million, three hundred seventeen thousand, seven hundred thirty-two".