31897242 has 48 divisors (see below), whose sum is σ = 74850048. Its totient is φ = 9758880.

The previous prime is 31897231. The next prime is 31897259. The reversal of 31897242 is 24279813.

It is a junction number, because it is equal to n+sod(n) for n = 31897197 and 31897206.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 63163 + ... + 63665.

It is an arithmetic number, because the mean of its divisors is an integer number (1559376).

Almost surely, 2^31897242 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31897242, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37425024).

31897242 is an abundant number, since it is smaller than the sum of its proper divisors (42952806).

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

31897242 is a wasteful number, since it uses less digits than its factorization.

31897242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 795 (or 792 counting only the distinct ones).

The product of its digits is 24192, while the sum is 36.

The square root of 31897242 is about 5647.7643364432. The cubic root of 31897242 is about 317.1400164969.

The spelling of 31897242 in words is "thirty-one million, eight hundred ninety-seven thousand, two hundred forty-two".