21339312 has 20 divisors (see below), whose sum is σ = 55126680. Its totient is φ = 7113088.

The previous prime is 21339293. The next prime is 21339313. The reversal of 21339312 is 21393312.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is not an unprimeable number, because it can be changed into a prime (21339313) 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, 222237 + ... + 222332.

It is an arithmetic number, because the mean of its divisors is an integer number (2756334).

Almost surely, 2^21339312 is an apocalyptic number.

It is an amenable number.

21339312 is an abundant number, since it is smaller than the sum of its proper divisors (33787368).

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

21339312 is a wasteful number, since it uses less digits than its factorization.

21339312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 444580 (or 444574 counting only the distinct ones).

The product of its digits is 972, while the sum is 24.

The square root of 21339312 is about 4619.4493178300. The cubic root of 21339312 is about 277.3704159200.

The spelling of 21339312 in words is "twenty-one million, three hundred thirty-nine thousand, three hundred twelve".