1331440 has 80 divisors (see below), whose sum is σ = 3615840. Its totient is φ = 450560.

The previous prime is 1331437. The next prime is 1331443. The reversal of 1331440 is 441331.

It is an interprime number because it is at equal distance from previous prime (1331437) and next prime (1331443).

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 (16).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1331443) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14916 + ... + 15004.

It is an arithmetic number, because the mean of its divisors is an integer number (45198).

2^1331440 is an apocalyptic number.

1331440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1331440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1807920).

1331440 is an abundant number, since it is smaller than the sum of its proper divisors (2284400).

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

1331440 is a wasteful number, since it uses less digits than its factorization.

1331440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130 (or 124 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 1331440 is about 1153.8804097479. The cubic root of 1331440 is about 110.0121198767.

Adding to 1331440 its reverse (441331), we get a palindrome (1772771).

It can be divided in two parts, 1331 and 440, that added together give a palindrome (1771).

The spelling of 1331440 in words is "one million, three hundred thirty-one thousand, four hundred forty".