31644763081 has 2 divisors, whose sum is σ = 31644763082. Its totient is φ = 31644763080.

The previous prime is 31644763069. The next prime is 31644763091. The reversal of 31644763081 is 18036744613.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25798784400 + 5845978681 = 160620^2 + 76459^2 .

It is a cyclic number.

It is not a de Polignac number, because 31644763081 - 2²⁹ = 31107892169 is a prime.

It is a super-2 number, since 2×31644763081² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (31644763001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15822381540 + 15822381541.

It is an arithmetic number, because the mean of its divisors is an integer number (15822381541).

Almost surely, 2^31644763081 is an apocalyptic number.

It is an amenable number.

31644763081 is a deficient number, since it is larger than the sum of its proper divisors (1).

31644763081 is an equidigital number, since it uses as much as digits as its factorization.

31644763081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 290304, while the sum is 43.

The spelling of 31644763081 in words is "thirty-one billion, six hundred forty-four million, seven hundred sixty-three thousand, eighty-one".