21631452465047 has 2 divisors, whose sum is σ = 21631452465048. Its totient is φ = 21631452465046.

The previous prime is 21631452465041. The next prime is 21631452465071. The reversal of 21631452465047 is 74056425413612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21631452465047 - 2¹⁸ = 21631452202903 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21631452464986 and 21631452465004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21631452465041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10815726232523 + 10815726232524.

It is an arithmetic number, because the mean of its divisors is an integer number (10815726232524).

Almost surely, 2^{21631452465047} is an apocalyptic number.

21631452465047 is a deficient number, since it is larger than the sum of its proper divisors (1).

21631452465047 is an equidigital number, since it uses as much as digits as its factorization.

21631452465047 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4838400, while the sum is 50.

Adding to 21631452465047 its reverse (74056425413612), we get a palindrome (95687877878659).

The spelling of 21631452465047 in words is "twenty-one trillion, six hundred thirty-one billion, four hundred fifty-two million, four hundred sixty-five thousand, forty-seven".