21979752 has 32 divisors (see below), whose sum is σ = 55773600. Its totient is φ = 7216704.

The previous prime is 21979733. The next prime is 21979753. The reversal of 21979752 is 25797912.

It is not an unprimeable number, because it can be changed into a prime (21979753) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5227 + ... + 8442.

It is an arithmetic number, because the mean of its divisors is an integer number (1742925).

Almost surely, 2^21979752 is an apocalyptic number.

It is an amenable number.

21979752 is an abundant number, since it is smaller than the sum of its proper divisors (33793848).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21979752 is a wasteful number, since it uses less digits than its factorization.

21979752 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13745 (or 13741 counting only the distinct ones).

The product of its digits is 79380, while the sum is 42.

The square root of 21979752 is about 4688.2568189040. The cubic root of 21979752 is about 280.1179435093.

The spelling of 21979752 in words is "twenty-one million, nine hundred seventy-nine thousand, seven hundred fifty-two".