311608501891 has 4 divisors (see below), whose sum is σ = 313474421232. Its totient is φ = 309742582552.

The previous prime is 311608501871. The next prime is 311608501901. The reversal of 311608501891 is 198105806113.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 311608501891 - 2²⁵ = 311574947459 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (311608501871) 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, 932959420 + ... + 932959753.

It is an arithmetic number, because the mean of its divisors is an integer number (78368605308).

Almost surely, 2^311608501891 is an apocalyptic number.

311608501891 is a deficient number, since it is larger than the sum of its proper divisors (1865919341).

311608501891 is a wasteful number, since it uses less digits than its factorization.

311608501891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1865919340.

The product of its (nonzero) digits is 51840, while the sum is 43.

The spelling of 311608501891 in words is "three hundred eleven billion, six hundred eight million, five hundred one thousand, eight hundred ninety-one".