311393840 has 40 divisors (see below), whose sum is σ = 729715200. Its totient is φ = 123572736.

The previous prime is 311393827. The next prime is 311393881. The reversal of 311393840 is 48393113.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×311393840² = 193932247179891200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 311393797 and 311393806.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5165 + ... + 25484.

It is an arithmetic number, because the mean of its divisors is an integer number (18242880).

Almost surely, 2^311393840 is an apocalyptic number.

It is an amenable number.

311393840 is an abundant number, since it is smaller than the sum of its proper divisors (418321360).

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

311393840 is a wasteful number, since it uses less digits than its factorization.

311393840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30789 (or 30783 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 311393840 is about 17646.3548643905. The cubic root of 311393840 is about 677.8027695006.

The spelling of 311393840 in words is "three hundred eleven million, three hundred ninety-three thousand, eight hundred forty".