311918981957 has 4 divisors (see below), whose sum is σ = 340275253056. Its totient is φ = 283562710860.

The previous prime is 311918981939. The next prime is 311918981989. The reversal of 311918981957 is 759189819113.

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: 759189819113 = 11 ⋅69017256283.

It is not a de Polignac number, because 311918981957 - 2³⁰ = 310845240133 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 311918981957.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (311918981657) 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, 14178135533 + ... + 14178135554.

It is an arithmetic number, because the mean of its divisors is an integer number (85068813264).

Almost surely, 2^311918981957 is an apocalyptic number.

It is an amenable number.

311918981957 is a deficient number, since it is larger than the sum of its proper divisors (28356271099).

311918981957 is a wasteful number, since it uses less digits than its factorization.

311918981957 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28356271098.

The product of its digits is 4898880, while the sum is 62.

The spelling of 311918981957 in words is "three hundred eleven billion, nine hundred eighteen million, nine hundred eighty-one thousand, nine hundred fifty-seven".