31740081561 has 6 divisors (see below), whose sum is σ = 45846784490. Its totient is φ = 21160054368.

The previous prime is 31740081553. The next prime is 31740081577. The reversal of 31740081561 is 16518004713.

31740081561 is a `hidden beast` number, since 3 + 17 + 4 + 0 + 0 + 81 + 561 = 666.

It can be written as a sum of positive squares in only one way, i.e., 29085255936 + 2654825625 = 170544^2 + 51525^2 .

It is not a de Polignac number, because 31740081561 - 2³ = 31740081553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31740083561) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1763337856 + ... + 1763337873.

Almost surely, 2^31740081561 is an apocalyptic number.

It is an amenable number.

31740081561 is a deficient number, since it is larger than the sum of its proper divisors (14106702929).

31740081561 is a wasteful number, since it uses less digits than its factorization.

31740081561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3526675735 (or 3526675732 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The spelling of 31740081561 in words is "thirty-one billion, seven hundred forty million, eighty-one thousand, five hundred sixty-one".