161631447713 has 12 divisors (see below), whose sum is σ = 168264647148. Its totient is φ = 155249203200.

The previous prime is 161631447701. The next prime is 161631447751. The reversal of 161631447713 is 317744136161.

It can be written as a sum of positive squares in 6 ways, for example, as 6728592784 + 154902854929 = 82028^2 + 393577^2 .

It is not a de Polignac number, because 161631447713 - 2²⁸ = 161363012257 is a prime.

It is a super-2 number, since 2×161631447713² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (161631447763) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 335588 + ... + 660213.

It is an arithmetic number, because the mean of its divisors is an integer number (14022053929).

Almost surely, 2^161631447713 is an apocalyptic number.

It is an amenable number.

161631447713 is a deficient number, since it is larger than the sum of its proper divisors (6633199435).

161631447713 is an equidigital number, since it uses as much as digits as its factorization.

161631447713 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 996052 (or 996023 counting only the distinct ones).

The product of its digits is 254016, while the sum is 44.

The spelling of 161631447713 in words is "one hundred sixty-one billion, six hundred thirty-one million, four hundred forty-seven thousand, seven hundred thirteen".