31212313 has 6 divisors (see below), whose sum is σ = 34307882. Its totient is φ = 28374720.

The previous prime is 31212301. The next prime is 31212341. The reversal of 31212313 is 31321213.

It can be written as a sum of positive squares in only one way, i.e., 20539024 + 10673289 = 4532^2 + 3267^2 .

It is a de Polignac number, because none of the positive numbers 2^k-31212313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31212343) 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, 128856 + ... + 129097.

Almost surely, 2^31212313 is an apocalyptic number.

It is an amenable number.

31212313 is a deficient number, since it is larger than the sum of its proper divisors (3095569).

31212313 is a wasteful number, since it uses less digits than its factorization.

31212313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257975 (or 257964 counting only the distinct ones).

The product of its digits is 108, while the sum is 16.

The square root of 31212313 is about 5586.7980990904. The cubic root of 31212313 is about 314.8535911532.

Adding to 31212313 its reverse (31321213), we get a palindrome (62533526).

Subtracting 31212313 from its reverse (31321213), we obtain a square (108900 = 330²).

The spelling of 31212313 in words is "thirty-one million, two hundred twelve thousand, three hundred thirteen".