21966359 has 2 divisors, whose sum is σ = 21966360. Its totient is φ = 21966358.

The previous prime is 21966331. The next prime is 21966401. The reversal of 21966359 is 95366912.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21966359 - 2⁸ = 21966103 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 (21906359) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10983179 + 10983180.

It is an arithmetic number, because the mean of its divisors is an integer number (10983180).

Almost surely, 2^21966359 is an apocalyptic number.

21966359 is a deficient number, since it is larger than the sum of its proper divisors (1).

21966359 is an equidigital number, since it uses as much as digits as its factorization.

21966359 is an evil number, because the sum of its binary digits is even.

The product of its digits is 87480, while the sum is 41.

The square root of 21966359 is about 4686.8282451995. The cubic root of 21966359 is about 280.0610368637.

The spelling of 21966359 in words is "twenty-one million, nine hundred sixty-six thousand, three hundred fifty-nine".