31761619081 has 2 divisors, whose sum is σ = 31761619082. Its totient is φ = 31761619080.

The previous prime is 31761619079. The next prime is 31761619091. The reversal of 31761619081 is 18091616713.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29405390400 + 2356228681 = 171480^2 + 48541^2 .

It is a cyclic number.

It is not a de Polignac number, because 31761619081 - 2¹ = 31761619079 is a prime.

It is a super-2 number, since 2×31761619081² (a number of 22 digits) contains 22 as substring.

Together with 31761619079, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (31761619091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15880809540 + 15880809541.

It is an arithmetic number, because the mean of its divisors is an integer number (15880809541).

Almost surely, 2^31761619081 is an apocalyptic number.

It is an amenable number.

31761619081 is a deficient number, since it is larger than the sum of its proper divisors (1).

31761619081 is an equidigital number, since it uses as much as digits as its factorization.

31761619081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 54432, while the sum is 43.

The spelling of 31761619081 in words is "thirty-one billion, seven hundred sixty-one million, six hundred nineteen thousand, eighty-one".