31607561687 has 4 divisors (see below), whose sum is σ = 34038912600. Its totient is φ = 29176210776.

The previous prime is 31607561669. The next prime is 31607561747. The reversal of 31607561687 is 78616570613.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 31607561687 - 2⁸ = 31607561431 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 (31607551687) 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, 1215675437 + ... + 1215675462.

It is an arithmetic number, because the mean of its divisors is an integer number (8509728150).

Almost surely, 2^31607561687 is an apocalyptic number.

31607561687 is a deficient number, since it is larger than the sum of its proper divisors (2431350913).

31607561687 is a wasteful number, since it uses less digits than its factorization.

31607561687 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2431350912.

The product of its (nonzero) digits is 1270080, while the sum is 50.

The spelling of 31607561687 in words is "thirty-one billion, six hundred seven million, five hundred sixty-one thousand, six hundred eighty-seven".