21632970 has 32 divisors (see below), whose sum is σ = 52073280. Its totient is φ = 5751680.

The previous prime is 21632921. The next prime is 21632983. The reversal of 21632970 is 7923612.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11710 + ... + 13430.

It is an arithmetic number, because the mean of its divisors is an integer number (1627290).

Almost surely, 2^21632970 is an apocalyptic number.

21632970 is an abundant number, since it is smaller than the sum of its proper divisors (30440310).

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

21632970 is a wasteful number, since it uses less digits than its factorization.

21632970 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2150.

The product of its (nonzero) digits is 4536, while the sum is 30.

The square root of 21632970 is about 4651.1256702007. The cubic root of 21632970 is about 278.6369553752.

The spelling of 21632970 in words is "twenty-one million, six hundred thirty-two thousand, nine hundred seventy".