21900933 has 12 divisors (see below), whose sum is σ = 32036160. Its totient is φ = 14415336.

The previous prime is 21900883. The next prime is 21900937. The reversal of 21900933 is 33900912.

It is not a de Polignac number, because 21900933 - 2⁸ = 21900677 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21900897 and 21900906.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21900937) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 14691 + ... + 16112.

It is an arithmetic number, because the mean of its divisors is an integer number (2669680).

Almost surely, 2^21900933 is an apocalyptic number.

It is an amenable number.

21900933 is a deficient number, since it is larger than the sum of its proper divisors (10135227).

21900933 is a wasteful number, since it uses less digits than its factorization.

21900933 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30888 (or 30885 counting only the distinct ones).

The product of its (nonzero) digits is 1458, while the sum is 27.

The square root of 21900933 is about 4679.8432666063. The cubic root of 21900933 is about 279.7827098199.

The spelling of 21900933 in words is "twenty-one million, nine hundred thousand, nine hundred thirty-three".