311143120 has 20 divisors (see below), whose sum is σ = 723407940. Its totient is φ = 124457216.

The previous prime is 311143111. The next prime is 311143123. The reversal of 311143120 is 21341113.

It can be written as a sum of positive squares in 2 ways, for example, as 44408896 + 266734224 = 6664^2 + 16332^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a super-2 number, since 2×311143120² = 193620082246668800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a junction number, because it is equal to n+sod(n) for n = 311143094 and 311143103.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (311143123) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 1944565 + ... + 1944724.

It is an arithmetic number, because the mean of its divisors is an integer number (36170397).

Almost surely, 2^311143120 is an apocalyptic number.

It is an amenable number.

311143120 is an abundant number, since it is smaller than the sum of its proper divisors (412264820).

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

311143120 is a wasteful number, since it uses less digits than its factorization.

311143120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3889302 (or 3889296 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 311143120 is about 17639.2494171379. The cubic root of 311143120 is about 677.6208087830.

Adding to 311143120 its reverse (21341113), we get a palindrome (332484233).

The spelling of 311143120 in words is "three hundred eleven million, one hundred forty-three thousand, one hundred twenty".