311213231 has 16 divisors (see below), whose sum is σ = 368358144. Its totient is φ = 257390784.

The previous prime is 311213213. The next prime is 311213251. The reversal of 311213231 is 132312113.

It is a de Polignac number, because none of the positive numbers 2^k-311213231 is a prime.

It is a super-2 number, since 2×311213231² = 193707350298918722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (311213251) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18755 + ... + 31211.

It is an arithmetic number, because the mean of its divisors is an integer number (23022384).

Almost surely, 2^311213231 is an apocalyptic number.

311213231 is a deficient number, since it is larger than the sum of its proper divisors (57144913).

311213231 is a wasteful number, since it uses less digits than its factorization.

311213231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12590.

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

The square root of 311213231 is about 17641.2366630007. The cubic root of 311213231 is about 677.6717018731.

Adding to 311213231 its reverse (132312113), we get a palindrome (443525344).

The spelling of 311213231 in words is "three hundred eleven million, two hundred thirteen thousand, two hundred thirty-one".