21631599767 has 2 divisors, whose sum is σ = 21631599768. Its totient is φ = 21631599766.

The previous prime is 21631599727. The next prime is 21631599779. The reversal of 21631599767 is 76799513612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21631599767 - 2¹⁴ = 21631583383 is a prime.

It is a super-2 number, since 2×21631599767² (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 (21631599707) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10815799883 + 10815799884.

It is an arithmetic number, because the mean of its divisors is an integer number (10815799884).

Almost surely, 2^21631599767 is an apocalyptic number.

21631599767 is a deficient number, since it is larger than the sum of its proper divisors (1).

21631599767 is an equidigital number, since it uses as much as digits as its factorization.

21631599767 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4286520, while the sum is 56.

The spelling of 21631599767 in words is "twenty-one billion, six hundred thirty-one million, five hundred ninety-nine thousand, seven hundred sixty-seven".