21925760 has 32 divisors (see below), whose sum is σ = 52417800. Its totient is φ = 8770048.

The previous prime is 21925759. The next prime is 21925763. The reversal of 21925760 is 6752912.

It is a tau number, because it is divible by the number of its divisors (32).

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21925763) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16490 + ... + 17769.

Almost surely, 2^21925760 is an apocalyptic number.

21925760 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21925760 is an abundant number, since it is smaller than the sum of its proper divisors (30492040).

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

21925760 is an equidigital number, since it uses as much as digits as its factorization.

21925760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34278 (or 34266 counting only the distinct ones).

The product of its (nonzero) digits is 7560, while the sum is 32.

The square root of 21925760 is about 4682.4950613962. The cubic root of 21925760 is about 279.8883908922. Note that the first 3 decimals are identical.

The spelling of 21925760 in words is "twenty-one million, nine hundred twenty-five thousand, seven hundred sixty".