21093636 has 24 divisors (see below), whose sum is σ = 49327264. Its totient is φ = 7015680.

The previous prime is 21093613. The next prime is 21093661. The reversal of 21093636 is 63639012.

It is a happy number.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors.

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, 4596 + ... + 7956.

Almost surely, 2^21093636 is an apocalyptic number.

It is an amenable number.

21093636 is an abundant number, since it is smaller than the sum of its proper divisors (28233628).

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

21093636 is a wasteful number, since it uses less digits than its factorization.

21093636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3891 (or 3889 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 30.

The square root of 21093636 is about 4592.7808569537. The cubic root of 21093636 is about 276.3018646435.

The spelling of 21093636 in words is "twenty-one million, ninety-three thousand, six hundred thirty-six".