311432240 has 120 divisors (see below), whose sum is σ = 858762000. Its totient is φ = 104692224.

The previous prime is 311432221. The next prime is 311432243. The reversal of 311432240 is 42234113.

It is a super-2 number, since 2×311432240² = 193980080222835200, which contains 22 as substring.

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 (311432243) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 207011 + ... + 208509.

It is an arithmetic number, because the mean of its divisors is an integer number (7156350).

Almost surely, 2^311432240 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 311432240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (429381000).

311432240 is an abundant number, since it is smaller than the sum of its proper divisors (547329760).

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

311432240 is a wasteful number, since it uses less digits than its factorization.

311432240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1579 (or 1566 counting only the distinct ones).

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

The square root of 311432240 is about 17647.4428742523. The cubic root of 311432240 is about 677.8306297783.

Adding to 311432240 its reverse (42234113), we get a palindrome (353666353).

The spelling of 311432240 in words is "three hundred eleven million, four hundred thirty-two thousand, two hundred forty".