311988681 has 24 divisors (see below), whose sum is σ = 466119680. Its totient is φ = 200880000.

The previous prime is 311988659. The next prime is 311988689. The reversal of 311988681 is 186889113.

It is not a de Polignac number, because 311988681 - 2¹³ = 311980489 is a prime.

It is a super-2 number, since 2×311988681² = 194673874144239522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (311988689) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 208785 + ... + 210273.

Almost surely, 2^311988681 is an apocalyptic number.

311988681 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

It is an amenable number.

311988681 is a deficient number, since it is larger than the sum of its proper divisors (154130999).

311988681 is a wasteful number, since it uses less digits than its factorization.

311988681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2277 (or 2274 counting only the distinct ones).

The product of its digits is 82944, while the sum is 45.

The square root of 311988681 is about 17663.2013236559. The cubic root of 311988681 is about 678.2340865544.

The spelling of 311988681 in words is "three hundred eleven million, nine hundred eighty-eight thousand, six hundred eighty-one".