21675560 has 16 divisors (see below), whose sum is σ = 48770100. Its totient is φ = 8670208.

The previous prime is 21675559. The next prime is 21675571. The reversal of 21675560 is 6557612.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 20052484 + 1623076 = 4478^2 + 1274^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 270905 + ... + 270984.

Almost surely, 2^21675560 is an apocalyptic number.

21675560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21675560 is an abundant number, since it is smaller than the sum of its proper divisors (27094540).

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

21675560 is a wasteful number, since it uses less digits than its factorization.

21675560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 541900 (or 541896 counting only the distinct ones).

The product of its (nonzero) digits is 12600, while the sum is 32.

The square root of 21675560 is about 4655.7018804902. The cubic root of 21675560 is about 278.8196913965.

The spelling of 21675560 in words is "twenty-one million, six hundred seventy-five thousand, five hundred sixty".