21331930 has 16 divisors (see below), whose sum is σ = 38548224. Its totient is φ = 8499280.

The previous prime is 21331903. The next prime is 21331963. The reversal of 21331930 is 3913312.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1426 + ... + 6685.

It is an arithmetic number, because the mean of its divisors is an integer number (2409264).

Almost surely, 2^21331930 is an apocalyptic number.

21331930 is a deficient number, since it is larger than the sum of its proper divisors (17216294).

21331930 is a wasteful number, since it uses less digits than its factorization.

21331930 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8381.

The product of its (nonzero) digits is 486, while the sum is 22.

The square root of 21331930 is about 4618.6502357290. The cubic root of 21331930 is about 277.3384282507.

The spelling of 21331930 in words is "twenty-one million, three hundred thirty-one thousand, nine hundred thirty".