31686342 has 8 divisors (see below), whose sum is σ = 63372696. Its totient is φ = 10562112.

The previous prime is 31686289. The next prime is 31686349. The reversal of 31686342 is 24368613.

It is a sphenic number, since it is the product of 3 distinct primes.

31686342 is an admirable number.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31686349) 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, 2640523 + ... + 2640534.

It is an arithmetic number, because the mean of its divisors is an integer number (7921587).

Almost surely, 2^31686342 is an apocalyptic number.

31686342 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31686342 is a wasteful number, since it uses less digits than its factorization.

31686342 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5281062.

The product of its digits is 20736, while the sum is 33.

The square root of 31686342 is about 5629.0622664881. The cubic root of 31686342 is about 316.4395088654.

The spelling of 31686342 in words is "thirty-one million, six hundred eighty-six thousand, three hundred forty-two".