21533488 has 20 divisors (see below), whose sum is σ = 42407008. Its totient is φ = 10589760.

The previous prime is 21533471. The next prime is 21533507. The reversal of 21533488 is 88433512.

It is a happy number.

It is a super-2 number, since 2×21533488² = 927382210892288, which contains 22 as substring.

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, 10056 + ... + 12007.

Almost surely, 2^21533488 is an apocalyptic number.

It is an amenable number.

21533488 is a deficient number, since it is larger than the sum of its proper divisors (20873520).

21533488 is a wasteful number, since it uses less digits than its factorization.

21533488 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22132 (or 22126 counting only the distinct ones).

The product of its digits is 23040, while the sum is 34.

The square root of 21533488 is about 4640.4189466039. The cubic root of 21533488 is about 278.2091830007.

The spelling of 21533488 in words is "twenty-one million, five hundred thirty-three thousand, four hundred eighty-eight".