21338312 has 8 divisors (see below), whose sum is σ = 40009350. Its totient is φ = 10669152.

The previous prime is 21338299. The next prime is 21338321. The reversal of 21338312 is 21383312.

It can be written as a sum of positive squares in only one way, i.e., 21031396 + 306916 = 4586^2 + 554^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1333637 + ... + 1333652.

Almost surely, 2^21338312 is an apocalyptic number.

It is an amenable number.

21338312 is a deficient number, since it is larger than the sum of its proper divisors (18671038).

21338312 is a wasteful number, since it uses less digits than its factorization.

21338312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2667295 (or 2667291 counting only the distinct ones).

The product of its digits is 864, while the sum is 23.

The square root of 21338312 is about 4619.3410785522. The cubic root of 21338312 is about 277.3660831538.

The spelling of 21338312 in words is "twenty-one million, three hundred thirty-eight thousand, three hundred twelve".