21944759 has 2 divisors, whose sum is σ = 21944760. Its totient is φ = 21944758.

The previous prime is 21944701. The next prime is 21944777. The reversal of 21944759 is 95744912.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21944759 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21944789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10972379 + 10972380.

It is an arithmetic number, because the mean of its divisors is an integer number (10972380).

Almost surely, 2^21944759 is an apocalyptic number.

21944759 is a deficient number, since it is larger than the sum of its proper divisors (1).

21944759 is an equidigital number, since it uses as much as digits as its factorization.

21944759 is an evil number, because the sum of its binary digits is even.

The product of its digits is 90720, while the sum is 41.

The square root of 21944759 is about 4684.5233482180. The cubic root of 21944759 is about 279.9692100497.

The spelling of 21944759 in words is "twenty-one million, nine hundred forty-four thousand, seven hundred fifty-nine".