21339328 has 14 divisors (see below), whose sum is σ = 42345356. Its totient is φ = 10669632.

The previous prime is 21339323. The next prime is 21339349. The reversal of 21339328 is 82393312.

It is a self number, because there is not a number n which added to its sum of digits gives 21339328.

It is not an unprimeable number, because it can be changed into a prime (21339323) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 166650 + ... + 166777.

Almost surely, 2^21339328 is an apocalyptic number.

It is an amenable number.

21339328 is a deficient number, since it is larger than the sum of its proper divisors (21006028).

21339328 is an equidigital number, since it uses as much as digits as its factorization.

21339328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333439 (or 333429 counting only the distinct ones).

The product of its digits is 7776, while the sum is 31.

The square root of 21339328 is about 4619.4510496378. The cubic root of 21339328 is about 277.3704852431.

The spelling of 21339328 in words is "twenty-one million, three hundred thirty-nine thousand, three hundred twenty-eight".