331440 has 40 divisors (see below), whose sum is σ = 1028208. Its totient is φ = 88320.

The previous prime is 331423. The next prime is 331447. The reversal of 331440 is 44133.

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

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 331440.

It is not an unprimeable number, because it can be changed into a prime (331447) by changing a digit.

331440 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 451 + ... + 930.

2³³¹⁴⁴⁰ is an apocalyptic number.

331440 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

331440 is an abundant number, since it is smaller than the sum of its proper divisors (696768).

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

331440 is a wasteful number, since it uses less digits than its factorization.

331440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1397 (or 1391 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 15.

The square root of 331440 is about 575.7082594509. The cubic root of 331440 is about 69.2046016965.

Adding to 331440 its reverse (44133), we get a palindrome (375573).

The spelling of 331440 in words is "three hundred thirty-one thousand, four hundred forty".