311223440 has 80 divisors (see below), whose sum is σ = 799073856. Its totient is φ = 111782400.

The previous prime is 311223427. The next prime is 311223443. The reversal of 311223440 is 44322113.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (311223443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 70910 + ... + 75170.

Almost surely, 2^311223440 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 311223440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (399536928).

311223440 is an abundant number, since it is smaller than the sum of its proper divisors (487850416).

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

311223440 is a wasteful number, since it uses less digits than its factorization.

311223440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4368 (or 4362 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

The square root of 311223440 is about 17641.5260110910. The cubic root of 311223440 is about 677.6791118781.

Adding to 311223440 its reverse (44322113), we get a palindrome (355545553).

The spelling of 311223440 in words is "three hundred eleven million, two hundred twenty-three thousand, four hundred forty".