311991120 has 240 divisors, whose sum is σ = 1211089152. Its totient is φ = 70502400.

The previous prime is 311991109. The next prime is 311991131. The reversal of 311991120 is 21199113.

It is an interprime number because it is at equal distance from previous prime (311991109) and next prime (311991131).

It is a tau number, because it is divible by the number of its divisors (240).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 518820 + ... + 519420.

Almost surely, 2^311991120 is an apocalyptic number.

311991120 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 311991120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (605544576).

311991120 is an abundant number, since it is smaller than the sum of its proper divisors (899098032).

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

311991120 is a wasteful number, since it uses less digits than its factorization.

311991120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 730 (or 721 counting only the distinct ones).

The product of its (nonzero) digits is 486, while the sum is 27.

The square root of 311991120 is about 17663.2703653655. The cubic root of 311991120 is about 678.2358539355.

The spelling of 311991120 in words is "three hundred eleven million, nine hundred ninety-one thousand, one hundred twenty".