21145697659 has 2 divisors, whose sum is σ = 21145697660. Its totient is φ = 21145697658.

The previous prime is 21145697653. The next prime is 21145697663. The reversal of 21145697659 is 95679654112.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21145697659 is a prime.

It is not a weakly prime, because it can be changed into another prime (21145697653) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10572848829 + 10572848830.

It is an arithmetic number, because the mean of its divisors is an integer number (10572848830).

Almost surely, 2^21145697659 is an apocalyptic number.

21145697659 is a deficient number, since it is larger than the sum of its proper divisors (1).

21145697659 is an equidigital number, since it uses as much as digits as its factorization.

21145697659 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4082400, while the sum is 55.

The spelling of 21145697659 in words is "twenty-one billion, one hundred forty-five million, six hundred ninety-seven thousand, six hundred fifty-nine".