31303312213 has 4 divisors (see below), whose sum is σ = 31303938988. Its totient is φ = 31302685440.

The previous prime is 31303312169. The next prime is 31303312237. The reversal of 31303312213 is 31221330313.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 17562080484 + 13741231729 = 132522^2 + 117223^2 .

It is a cyclic number.

It is not a de Polignac number, because 31303312213 - 2¹⁷ = 31303181141 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31303312273) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 231306 + ... + 340747.

It is an arithmetic number, because the mean of its divisors is an integer number (7825984747).

Almost surely, 2^31303312213 is an apocalyptic number.

It is an amenable number.

31303312213 is a deficient number, since it is larger than the sum of its proper divisors (626775).

31303312213 is an equidigital number, since it uses as much as digits as its factorization.

31303312213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 626774.

The product of its (nonzero) digits is 972, while the sum is 22.

Adding to 31303312213 its reverse (31221330313), we get a palindrome (62524642526).

The spelling of 31303312213 in words is "thirty-one billion, three hundred three million, three hundred twelve thousand, two hundred thirteen".