311111213 has 4 divisors (see below), whose sum is σ = 355555680. Its totient is φ = 266666748.

The previous prime is 311111201. The next prime is 311111231. The reversal of 311111213 is 312111113.

It is a happy number.

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 an emirpimes, since its reverse is a distinct semiprime: 312111113 = 367 ⋅850439.

It is a cyclic number.

It is not a de Polignac number, because 311111213 - 2¹² = 311107117 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 (311111233) 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, 22222223 + ... + 22222236.

It is an arithmetic number, because the mean of its divisors is an integer number (88888920).

Almost surely, 2^311111213 is an apocalyptic number.

It is an amenable number.

311111213 is a deficient number, since it is larger than the sum of its proper divisors (44444467).

311111213 is an equidigital number, since it uses as much as digits as its factorization.

311111213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44444466.

The product of its digits is 18, while the sum is 14.

The square root of 311111213 is about 17638.3449620422. The cubic root of 311111213 is about 677.5976451810.

Adding to 311111213 its reverse (312111113), we get a palindrome (623222326).

The spelling of 311111213 in words is "three hundred eleven million, one hundred eleven thousand, two hundred thirteen".