21331132 has 12 divisors (see below), whose sum is σ = 37524256. Its totient is φ = 10609920.

The previous prime is 21331127. The next prime is 21331133. The reversal of 21331132 is 23113312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21331133) 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, 13044 + ... + 14587.

Almost surely, 2^21331132 is an apocalyptic number.

It is an amenable number.

21331132 is a deficient number, since it is larger than the sum of its proper divisors (16193124).

21331132 is a wasteful number, since it uses less digits than its factorization.

21331132 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27828 (or 27826 counting only the distinct ones).

The product of its digits is 108, while the sum is 16.

The square root of 21331132 is about 4618.5638460457. The cubic root of 21331132 is about 277.3349699166.

Adding to 21331132 its reverse (23113312), we get a palindrome (44444444).

The spelling of 21331132 in words is "twenty-one million, three hundred thirty-one thousand, one hundred thirty-two".