31530242 has 4 divisors (see below), whose sum is σ = 47295366. Its totient is φ = 15765120.

The previous prime is 31530211. The next prime is 31530269. The reversal of 31530242 is 24203513.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24203513 = 37 ⋅654149.

It can be written as a sum of positive squares in only one way, i.e., 18054001 + 13476241 = 4249^2 + 3671^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7882559 + ... + 7882562.

Almost surely, 2^31530242 is an apocalyptic number.

31530242 is a deficient number, since it is larger than the sum of its proper divisors (15765124).

31530242 is a wasteful number, since it uses less digits than its factorization.

31530242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15765123.

The product of its (nonzero) digits is 720, while the sum is 20.

The square root of 31530242 is about 5615.1796053199. The cubic root of 31530242 is about 315.9190159936.

Adding to 31530242 its reverse (24203513), we get a palindrome (55733755).

The spelling of 31530242 in words is "thirty-one million, five hundred thirty thousand, two hundred forty-two".