31688603843 has 4 divisors (see below), whose sum is σ = 34126188768. Its totient is φ = 29251018920.

The previous prime is 31688603803. The next prime is 31688603851. The reversal of 31688603843 is 34830688613.

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 31688603843 - 2²⁰ = 31687555267 is a prime.

It is a super-2 number, since 2×31688603843² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31688603791 and 31688603800.

It is not an unprimeable number, because it can be changed into a prime (31688603803) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1218792443 + ... + 1218792468.

It is an arithmetic number, because the mean of its divisors is an integer number (8531547192).

Almost surely, 2^31688603843 is an apocalyptic number.

31688603843 is a deficient number, since it is larger than the sum of its proper divisors (2437584925).

31688603843 is a wasteful number, since it uses less digits than its factorization.

31688603843 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2437584924.

The product of its (nonzero) digits is 1990656, while the sum is 50.

The spelling of 31688603843 in words is "thirty-one billion, six hundred eighty-eight million, six hundred three thousand, eight hundred forty-three".