31861055217 has 16 divisors (see below), whose sum is σ = 44737160000. Its totient is φ = 20113821504.

The previous prime is 31861055209. The next prime is 31861055221. The reversal of 31861055217 is 71255016813.

It is not a de Polignac number, because 31861055217 - 2³ = 31861055209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31861055207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6159 + ... + 252507.

It is an arithmetic number, because the mean of its divisors is an integer number (2796072500).

Almost surely, 2^31861055217 is an apocalyptic number.

It is an amenable number.

31861055217 is a deficient number, since it is larger than the sum of its proper divisors (12876104783).

31861055217 is a wasteful number, since it uses less digits than its factorization.

31861055217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 248640.

The product of its (nonzero) digits is 50400, while the sum is 39.

The spelling of 31861055217 in words is "thirty-one billion, eight hundred sixty-one million, fifty-five thousand, two hundred seventeen".