311143140 has 288 divisors, whose sum is σ = 1229558400. Its totient is φ = 64592640.

The previous prime is 311143123. The next prime is 311143169. The reversal of 311143140 is 41341113.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 290526 + ... + 291594.

It is an arithmetic number, because the mean of its divisors is an integer number (4269300).

Almost surely, 2^311143140 is an apocalyptic number.

311143140 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

311143140 is the 8820-th decagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 311143140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (614779200).

311143140 is an abundant number, since it is smaller than the sum of its proper divisors (918415260).

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

311143140 is a wasteful number, since it uses less digits than its factorization.

311143140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1112 (or 1097 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 311143140 is about 17639.2499840554. The cubic root of 311143140 is about 677.6208233020.

Adding to 311143140 its reverse (41341113), we get a palindrome (352484253).

The spelling of 311143140 in words is "three hundred eleven million, one hundred forty-three thousand, one hundred forty".