21333986 has 16 divisors (see below), whose sum is σ = 32529336. Its totient is φ = 10492416.

The previous prime is 21333973. The next prime is 21334007. The reversal of 21333986 is 68933312.

It can be written as a sum of positive squares in 4 ways, for example, as 16248961 + 5085025 = 4031^2 + 2255^2 .

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, 53540 + ... + 53936.

Almost surely, 2^21333986 is an apocalyptic number.

21333986 is a deficient number, since it is larger than the sum of its proper divisors (11195350).

21333986 is a wasteful number, since it uses less digits than its factorization.

21333986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 773.

The product of its digits is 23328, while the sum is 35.

The square root of 21333986 is about 4618.8728062158. The cubic root of 21333986 is about 277.3473380476.

The spelling of 21333986 in words is "twenty-one million, three hundred thirty-three thousand, nine hundred eighty-six".