21959159 has 2 divisors, whose sum is σ = 21959160. Its totient is φ = 21959158.

The previous prime is 21959143. The next prime is 21959209. The reversal of 21959159 is 95195912.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21959159 - 2⁴ = 21959143 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21959659) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10979579 + 10979580.

It is an arithmetic number, because the mean of its divisors is an integer number (10979580).

Almost surely, 2^21959159 is an apocalyptic number.

21959159 is a deficient number, since it is larger than the sum of its proper divisors (1).

21959159 is an equidigital number, since it uses as much as digits as its factorization.

21959159 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36450, while the sum is 41.

The square root of 21959159 is about 4686.0600721715. The cubic root of 21959159 is about 280.0304346170.

The spelling of 21959159 in words is "twenty-one million, nine hundred fifty-nine thousand, one hundred fifty-nine".