21133232 has 20 divisors (see below), whose sum is σ = 41027136. Its totient is φ = 10545600.

The previous prime is 21133219. The next prime is 21133237. The reversal of 21133232 is 23233112.

It is a super-2 number, since 2×21133232² = 893226989531648, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21133232.

It is not an unprimeable number, because it can be changed into a prime (21133237) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9857 + ... + 11807.

Almost surely, 2^21133232 is an apocalyptic number.

It is an amenable number.

21133232 is a deficient number, since it is larger than the sum of its proper divisors (19893904).

21133232 is a wasteful number, since it uses less digits than its factorization.

21133232 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2636 (or 2630 counting only the distinct ones).

The product of its digits is 216, while the sum is 17.

The square root of 21133232 is about 4597.0895140295. The cubic root of 21133232 is about 276.4746436139.

Adding to 21133232 its reverse (23233112), we get a palindrome (44366344).

The spelling of 21133232 in words is "twenty-one million, one hundred thirty-three thousand, two hundred thirty-two".