311142991 has 8 divisors (see below), whose sum is σ = 313357680. Its totient is φ = 308933952.

The previous prime is 311142989. The next prime is 311143003. The reversal of 311142991 is 199241113.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 311142991 - 2¹ = 311142989 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 (311142191) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 216411 + ... + 217843.

It is an arithmetic number, because the mean of its divisors is an integer number (39169710).

Almost surely, 2^311142991 is an apocalyptic number.

311142991 is a deficient number, since it is larger than the sum of its proper divisors (2214689).

311142991 is a wasteful number, since it uses less digits than its factorization.

311142991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2825.

The product of its digits is 1944, while the sum is 31.

The square root of 311142991 is about 17639.2457605194. The cubic root of 311142991 is about 677.6207151358.

The spelling of 311142991 in words is "three hundred eleven million, one hundred forty-two thousand, nine hundred ninety-one".