31218242 has 12 divisors (see below), whose sum is σ = 51471798. Its totient is φ = 14190000.

The previous prime is 31218241. The next prime is 31218259. The reversal of 31218242 is 24281213.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 27762361 + 3455881 = 5269^2 + 1859^2 .

It is not an unprimeable number, because it can be changed into a prime (31218241) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 64259 + ... + 64742.

Almost surely, 2^31218242 is an apocalyptic number.

31218242 is a deficient number, since it is larger than the sum of its proper divisors (20253556).

31218242 is a wasteful number, since it uses less digits than its factorization.

31218242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129025 (or 129014 counting only the distinct ones).

The product of its digits is 768, while the sum is 23.

The square root of 31218242 is about 5587.3286998350. The cubic root of 31218242 is about 314.8735261145.

Adding to 31218242 its reverse (24281213), we get a palindrome (55499455).

The spelling of 31218242 in words is "thirty-one million, two hundred eighteen thousand, two hundred forty-two".