21425760 has 72 divisors (see below), whose sum is σ = 73120320. Its totient is φ = 5713152.

The previous prime is 21425759. The next prime is 21425773. The reversal of 21425760 is 6752412.

It is a tau number, because it is divible by the number of its divisors (72).

It is a super-3 number, since 3×21425760³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6000 + ... + 8879.

It is an arithmetic number, because the mean of its divisors is an integer number (1015560).

Almost surely, 2^21425760 is an apocalyptic number.

21425760 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21425760 is an abundant number, since it is smaller than the sum of its proper divisors (51694560).

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

21425760 is a wasteful number, since it uses less digits than its factorization.

21425760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14900 (or 14889 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

The square root of 21425760 is about 4628.7968199090. The cubic root of 21425760 is about 277.7444643901.

The spelling of 21425760 in words is "twenty-one million, four hundred twenty-five thousand, seven hundred sixty".