311312213 has 4 divisors (see below), whose sum is σ = 311347680. Its totient is φ = 311276748.

The previous prime is 311312203. The next prime is 311312227. The reversal of 311312213 is 312213113.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-311312213 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 311312191 and 311312200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (311312203) 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, 6206 + ... + 25712.

It is an arithmetic number, because the mean of its divisors is an integer number (77836920).

Almost surely, 2^311312213 is an apocalyptic number.

It is an amenable number.

311312213 is a deficient number, since it is larger than the sum of its proper divisors (35467).

311312213 is a wasteful number, since it uses less digits than its factorization.

311312213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35466.

The product of its digits is 108, while the sum is 17.

The square root of 311312213 is about 17644.0418555387. The cubic root of 311312213 is about 677.7435392112.

Adding to 311312213 its reverse (312213113), we get a palindrome (623525326).

The spelling of 311312213 in words is "three hundred eleven million, three hundred twelve thousand, two hundred thirteen".