21396933 has 8 divisors (see below), whose sum is σ = 31699200. Its totient is φ = 14264604.

The previous prime is 21396917. The next prime is 21396941. The reversal of 21396933 is 33969312.

It is a happy number.

It is not a de Polignac number, because 21396933 - 2⁴ = 21396917 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21396533) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 396213 + ... + 396266.

It is an arithmetic number, because the mean of its divisors is an integer number (3962400).

Almost surely, 2^21396933 is an apocalyptic number.

It is an amenable number.

21396933 is a deficient number, since it is larger than the sum of its proper divisors (10302267).

21396933 is an equidigital number, since it uses as much as digits as its factorization.

21396933 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 792488 (or 792482 counting only the distinct ones).

The product of its digits is 26244, while the sum is 36.

The square root of 21396933 is about 4625.6818956777. The cubic root of 21396933 is about 277.6198459694.

The spelling of 21396933 in words is "twenty-one million, three hundred ninety-six thousand, nine hundred thirty-three".