311218920 has 192 divisors, whose sum is σ = 1060300800. Its totient is φ = 79073280.

The previous prime is 311218903. The next prime is 311218937. The reversal of 311218920 is 29812113.

It is an interprime number because it is at equal distance from previous prime (311218903) and next prime (311218937).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 881464 + ... + 881816.

It is an arithmetic number, because the mean of its divisors is an integer number (5522400).

Almost surely, 2^311218920 is an apocalyptic number.

311218920 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 311218920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (530150400).

311218920 is an abundant number, since it is smaller than the sum of its proper divisors (749081880).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

311218920 is a wasteful number, since it uses less digits than its factorization.

311218920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 480 (or 473 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 311218920 is about 17641.3979037944. The cubic root of 311218920 is about 677.6758311436.

The spelling of 311218920 in words is "three hundred eleven million, two hundred eighteen thousand, nine hundred twenty".