31666687109 has 4 divisors (see below), whose sum is σ = 33043499616. Its totient is φ = 30289874604.

The previous prime is 31666687051. The next prime is 31666687153. The reversal of 31666687109 is 90178666613.

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.

It is a cyclic number.

It is not a de Polignac number, because 31666687109 - 2³² = 27371719813 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 (31666687189) 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, 688406219 + ... + 688406264.

It is an arithmetic number, because the mean of its divisors is an integer number (8260874904).

Almost surely, 2^31666687109 is an apocalyptic number.

It is an amenable number.

31666687109 is a deficient number, since it is larger than the sum of its proper divisors (1376812507).

31666687109 is a wasteful number, since it uses less digits than its factorization.

31666687109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1376812506.

The product of its (nonzero) digits is 1959552, while the sum is 53.

The spelling of 31666687109 in words is "thirty-one billion, six hundred sixty-six million, six hundred eighty-seven thousand, one hundred nine".