21339984 has 40 divisors (see below), whose sum is σ = 55313920. Its totient is φ = 7089408.

The previous prime is 21339979. The next prime is 21339991. The reversal of 21339984 is 48993312.

It is a congruent number.

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, 19089 + ... + 20175.

It is an arithmetic number, because the mean of its divisors is an integer number (1382848).

Almost surely, 2^21339984 is an apocalyptic number.

21339984 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21339984 is an abundant number, since it is smaller than the sum of its proper divisors (33973936).

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

21339984 is a wasteful number, since it uses less digits than its factorization.

21339984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1507 (or 1501 counting only the distinct ones).

The product of its digits is 46656, while the sum is 39.

The square root of 21339984 is about 4619.5220531999. The cubic root of 21339984 is about 277.3733274628.

The spelling of 21339984 in words is "twenty-one million, three hundred thirty-nine thousand, nine hundred eighty-four".