21887232 has 36 divisors (see below), whose sum is σ = 58254000. Its totient is φ = 7295488.

The previous prime is 21887231. The next prime is 21887233. The reversal of 21887232 is 23278812.

It is an interprime number because it is at equal distance from previous prime (21887231) and next prime (21887233).

It is a junction number, because it is equal to n+sod(n) for n = 21887193 and 21887202.

It is not an unprimeable number, because it can be changed into a prime (21887231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13482 + ... + 15017.

Almost surely, 2^21887232 is an apocalyptic number.

It is an amenable number.

21887232 is an abundant number, since it is smaller than the sum of its proper divisors (36366768).

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

21887232 is an equidigital number, since it uses as much as digits as its factorization.

21887232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28518 (or 28504 counting only the distinct ones).

The product of its digits is 10752, while the sum is 33.

The square root of 21887232 is about 4678.3792065201. The cubic root of 21887232 is about 279.7243545808.

The spelling of 21887232 in words is "twenty-one million, eight hundred eighty-seven thousand, two hundred thirty-two".