31705639679 has 12 divisors (see below), whose sum is σ = 38485640304. Its totient is φ = 25994685024.

The previous prime is 31705639643. The next prime is 31705639681. The reversal of 31705639679 is 97693650713.

It is a happy number.

It is not a de Polignac number, because 31705639679 - 2¹² = 31705635583 is a prime.

It is a Smith number, since the sum of its digits (56) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31705630679) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 14065262 + ... + 14067515.

It is an arithmetic number, because the mean of its divisors is an integer number (3207136692).

Almost surely, 2^31705639679 is an apocalyptic number.

31705639679 is a deficient number, since it is larger than the sum of its proper divisors (6780000625).

31705639679 is a wasteful number, since it uses less digits than its factorization.

31705639679 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28132814 (or 28132807 counting only the distinct ones).

The product of its (nonzero) digits is 6429780, while the sum is 56.

The spelling of 31705639679 in words is "thirty-one billion, seven hundred five million, six hundred thirty-nine thousand, six hundred seventy-nine".