21917423599 has 2 divisors, whose sum is σ = 21917423600. Its totient is φ = 21917423598.

The previous prime is 21917423573. The next prime is 21917423611. The reversal of 21917423599 is 99532471912.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21917423599 - 2¹³ = 21917415407 is a prime.

It is a super-2 number, since 2×21917423599² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21917423299) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10958711799 + 10958711800.

It is an arithmetic number, because the mean of its divisors is an integer number (10958711800).

Almost surely, 2^21917423599 is an apocalyptic number.

21917423599 is a deficient number, since it is larger than the sum of its proper divisors (1).

21917423599 is an equidigital number, since it uses as much as digits as its factorization.

21917423599 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1224720, while the sum is 52.

The spelling of 21917423599 in words is "twenty-one billion, nine hundred seventeen million, four hundred twenty-three thousand, five hundred ninety-nine".