31606718861 has 4 divisors (see below), whose sum is σ = 33270230400. Its totient is φ = 29943207324.

The previous prime is 31606718837. The next prime is 31606718893. The reversal of 31606718861 is 16881760613.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 16881760613 = 31 ⋅544572923.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31606718861 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31606718161) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 831755741 + ... + 831755778.

It is an arithmetic number, because the mean of its divisors is an integer number (8317557600).

Almost surely, 2^31606718861 is an apocalyptic number.

It is an amenable number.

31606718861 is a deficient number, since it is larger than the sum of its proper divisors (1663511539).

31606718861 is a wasteful number, since it uses less digits than its factorization.

31606718861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1663511538.

The product of its (nonzero) digits is 290304, while the sum is 47.

The spelling of 31606718861 in words is "thirty-one billion, six hundred six million, seven hundred eighteen thousand, eight hundred sixty-one".