31539942 has 96 divisors (see below), whose sum is σ = 82747392. Its totient is φ = 8817984.

The previous prime is 31539931. The next prime is 31539967. The reversal of 31539942 is 24993513.

It is a happy number.

31539942 is a `hidden beast` number, since 31 + 539 + 94 + 2 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 31539897 and 31539906.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 248283 + ... + 248409.

It is an arithmetic number, because the mean of its divisors is an integer number (861952).

Almost surely, 2^31539942 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31539942, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41373696).

31539942 is an abundant number, since it is smaller than the sum of its proper divisors (51207450).

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

31539942 is a wasteful number, since it uses less digits than its factorization.

31539942 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 224 (or 212 counting only the distinct ones).

The product of its digits is 29160, while the sum is 36.

The square root of 31539942 is about 5616.0432690641. The cubic root of 31539942 is about 315.9514092354.

The spelling of 31539942 in words is "thirty-one million, five hundred thirty-nine thousand, nine hundred forty-two".