31899242 has 24 divisors (see below), whose sum is σ = 51262860. Its totient is φ = 14883840.

The previous prime is 31899239. The next prime is 31899247. The reversal of 31899242 is 24299813.

It can be written as a sum of positive squares in 6 ways, for example, as 31595641 + 303601 = 5621^2 + 551^2 .

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 31899196 and 31899205.

It is not an unprimeable number, because it can be changed into a prime (31899247) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 132242 + ... + 132482.

Almost surely, 2^31899242 is an apocalyptic number.

31899242 is a deficient number, since it is larger than the sum of its proper divisors (19363618).

31899242 is a wasteful number, since it uses less digits than its factorization.

31899242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 506 (or 489 counting only the distinct ones).

The product of its digits is 31104, while the sum is 38.

The square root of 31899242 is about 5647.9413948801. The cubic root of 31899242 is about 317.1466447270.

The spelling of 31899242 in words is "thirty-one million, eight hundred ninety-nine thousand, two hundred forty-two".