31986943 has 4 divisors (see below), whose sum is σ = 32105248. Its totient is φ = 31868640.

The previous prime is 31986923. The next prime is 31986973. The reversal of 31986943 is 34968913.

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 31986943 - 2⁹ = 31986431 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 31986943.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31986923) 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, 58746 + ... + 59287.

It is an arithmetic number, because the mean of its divisors is an integer number (8026312).

Almost surely, 2^31986943 is an apocalyptic number.

31986943 is a deficient number, since it is larger than the sum of its proper divisors (118305).

31986943 is a wasteful number, since it uses less digits than its factorization.

31986943 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 118304.

The product of its digits is 139968, while the sum is 43.

The square root of 31986943 is about 5655.7000450873. The cubic root of 31986943 is about 317.4370239036.

The spelling of 31986943 in words is "thirty-one million, nine hundred eighty-six thousand, nine hundred forty-three".