21594959 has 2 divisors, whose sum is σ = 21594960. Its totient is φ = 21594958.

The previous prime is 21594931. The next prime is 21594973. The reversal of 21594959 is 95949512.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21594959 - 2¹⁶ = 21529423 is a 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 (21591959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10797479 + 10797480.

It is an arithmetic number, because the mean of its divisors is an integer number (10797480).

Almost surely, 2^21594959 is an apocalyptic number.

21594959 is a deficient number, since it is larger than the sum of its proper divisors (1).

21594959 is an equidigital number, since it uses as much as digits as its factorization.

21594959 is an evil number, because the sum of its binary digits is even.

The product of its digits is 145800, while the sum is 44.

The square root of 21594959 is about 4647.0376585520. The cubic root of 21594959 is about 278.4736632855.

The spelling of 21594959 in words is "twenty-one million, five hundred ninety-four thousand, nine hundred fifty-nine".