21732472 has 16 divisors (see below), whose sum is σ = 40863240. Its totient is φ = 10835616.

The previous prime is 21732439. The next prime is 21732481. The reversal of 21732472 is 27423712.

It is a self number, because there is not a number n which added to its sum of digits gives 21732472.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 658 + ... + 6625.

Almost surely, 2^21732472 is an apocalyptic number.

It is an amenable number.

21732472 is a deficient number, since it is larger than the sum of its proper divisors (19130768).

21732472 is a wasteful number, since it uses less digits than its factorization.

21732472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7662 (or 7658 counting only the distinct ones).

The product of its digits is 4704, while the sum is 28.

The square root of 21732472 is about 4661.8099489361. The cubic root of 21732472 is about 279.0635039133.

The spelling of 21732472 in words is "twenty-one million, seven hundred thirty-two thousand, four hundred seventy-two".