21630732 has 24 divisors (see below), whose sum is σ = 53441136. Its totient is φ = 6786048.

The previous prime is 21630727. The next prime is 21630733. The reversal of 21630732 is 23703612.

It is not an unprimeable number, because it can be changed into a prime (21630733) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 52813 + ... + 53220.

It is an arithmetic number, because the mean of its divisors is an integer number (2226714).

Almost surely, 2^21630732 is an apocalyptic number.

It is an amenable number.

21630732 is an abundant number, since it is smaller than the sum of its proper divisors (31810404).

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

21630732 is a wasteful number, since it uses less digits than its factorization.

21630732 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106057 (or 106055 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 24.

The square root of 21630732 is about 4650.8850770579. The cubic root of 21630732 is about 278.6273464155.

The spelling of 21630732 in words is "twenty-one million, six hundred thirty thousand, seven hundred thirty-two".