21669496591 has 2 divisors, whose sum is σ = 21669496592. Its totient is φ = 21669496590.

The previous prime is 21669496559. The next prime is 21669496613. The reversal of 21669496591 is 19569496612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21669496591 - 2⁵ = 21669496559 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21669496501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10834748295 + 10834748296.

It is an arithmetic number, because the mean of its divisors is an integer number (10834748296).

Almost surely, 2^21669496591 is an apocalyptic number.

21669496591 is a deficient number, since it is larger than the sum of its proper divisors (1).

21669496591 is an equidigital number, since it uses as much as digits as its factorization.

21669496591 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6298560, while the sum is 58.

The spelling of 21669496591 in words is "twenty-one billion, six hundred sixty-nine million, four hundred ninety-six thousand, five hundred ninety-one".