21925872 has 60 divisors (see below), whose sum is σ = 62806744. Its totient is φ = 7136640.

The previous prime is 21925853. The next prime is 21925879. The reversal of 21925872 is 27852912.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21925879) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4422 + ... + 7962.

Almost surely, 2^21925872 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21925872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31403372).

21925872 is an abundant number, since it is smaller than the sum of its proper divisors (40880872).

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

21925872 is a wasteful number, since it uses less digits than its factorization.

21925872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3598 (or 3589 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 21925872 is about 4682.5070208169. The cubic root of 21925872 is about 279.8888674617. Note that the first 4 decimals are identical.

The spelling of 21925872 in words is "twenty-one million, nine hundred twenty-five thousand, eight hundred seventy-two".