31121313213 has 8 divisors (see below), whose sum is σ = 41499158400. Its totient is φ = 20745505088.

The previous prime is 31121313193. The next prime is 31121313221. The reversal of 31121313213 is 31231312113.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 31121313213 - 2¹⁸ = 31121051069 is a prime.

It is a super-2 number, since 2×31121313213² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 31121313213.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31121313233) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 473253 + ... + 534986.

It is an arithmetic number, because the mean of its divisors is an integer number (5187394800).

Almost surely, 2^31121313213 is an apocalyptic number.

It is an amenable number.

31121313213 is a deficient number, since it is larger than the sum of its proper divisors (10377845187).

31121313213 is a wasteful number, since it uses less digits than its factorization.

31121313213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1018531.

The product of its digits is 324, while the sum is 21.

Adding to 31121313213 its reverse (31231312113), we get a palindrome (62352625326).

The spelling of 31121313213 in words is "thirty-one billion, one hundred twenty-one million, three hundred thirteen thousand, two hundred thirteen".