311319391 has 6 divisors (see below), whose sum is σ = 321463392. Its totient is φ = 301181760.

The previous prime is 311319383. The next prime is 311319401. The reversal of 311319391 is 193913113.

It is a happy number.

It is not a de Polignac number, because 311319391 - 2³ = 311319383 is a prime.

It is a super-2 number, since 2×311319391² = 193839526425221762, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (311319331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 96655 + ... + 99823.

It is an arithmetic number, because the mean of its divisors is an integer number (53577232).

Almost surely, 2^311319391 is an apocalyptic number.

311319391 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

311319391 is a deficient number, since it is larger than the sum of its proper divisors (10144001).

311319391 is an frugal number, since it uses more digits than its factorization.

311319391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6369 (or 3200 counting only the distinct ones).

The product of its digits is 2187, while the sum is 31.

The square root of 311319391 is about 17644.2452658083. The cubic root of 311319391 is about 677.7487481361.

Multiplying 311319391 by its sum of digits (31), we get a square (9650901121 = 98239²).

311319391 divided by its sum of digits (31) gives a square (10042561 = 3169²).

The spelling of 311319391 in words is "three hundred eleven million, three hundred nineteen thousand, three hundred ninety-one".