21336688 has 10 divisors (see below), whose sum is σ = 41339864. Its totient is φ = 10668336.

The previous prime is 21336671. The next prime is 21336697. The reversal of 21336688 is 88663312.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 666756 + ... + 666787.

Almost surely, 2^21336688 is an apocalyptic number.

It is an amenable number.

21336688 is a deficient number, since it is larger than the sum of its proper divisors (20003176).

21336688 is a wasteful number, since it uses less digits than its factorization.

21336688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1333551 (or 1333545 counting only the distinct ones).

The product of its digits is 41472, while the sum is 37.

The square root of 21336688 is about 4619.1652925610. The cubic root of 21336688 is about 277.3590464530.

The spelling of 21336688 in words is "twenty-one million, three hundred thirty-six thousand, six hundred eighty-eight".