21765933 has 24 divisors (see below), whose sum is σ = 38046528. Its totient is φ = 11705472.

The previous prime is 21765923. The next prime is 21765943. The reversal of 21765933 is 33956712.

It is an interprime number because it is at equal distance from previous prime (21765923) and next prime (21765943).

It is not a de Polignac number, because 21765933 - 2⁴ = 21765917 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21765923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9091 + ... + 11232.

It is an arithmetic number, because the mean of its divisors is an integer number (1585272).

Almost surely, 2^21765933 is an apocalyptic number.

It is an amenable number.

21765933 is a deficient number, since it is larger than the sum of its proper divisors (16280595).

21765933 is a wasteful number, since it uses less digits than its factorization.

21765933 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20353 (or 20350 counting only the distinct ones).

The product of its digits is 34020, while the sum is 36.

The square root of 21765933 is about 4665.3974107250. The cubic root of 21765933 is about 279.2066530778.

The spelling of 21765933 in words is "twenty-one million, seven hundred sixty-five thousand, nine hundred thirty-three".