21631563503129 has 2 divisors, whose sum is σ = 21631563503130. Its totient is φ = 21631563503128.

The previous prime is 21631563503087. The next prime is 21631563503159. The reversal of 21631563503129 is 92130536513612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12572378520025 + 9059184983104 = 3545755^2 + 3009848^2 .

It is a cyclic number.

It is not a de Polignac number, because 21631563503129 - 2²⁸ = 21631295067673 is a prime.

It is not a weakly prime, because it can be changed into another prime (21631563503159) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10815781751564 + 10815781751565.

It is an arithmetic number, because the mean of its divisors is an integer number (10815781751565).

Almost surely, 2^{21631563503129} is an apocalyptic number.

It is an amenable number.

21631563503129 is a deficient number, since it is larger than the sum of its proper divisors (1).

21631563503129 is an equidigital number, since it uses as much as digits as its factorization.

21631563503129 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 874800, while the sum is 47.

The spelling of 21631563503129 in words is "twenty-one trillion, six hundred thirty-one billion, five hundred sixty-three million, five hundred three thousand, one hundred twenty-nine".