1591440 has 80 divisors (see below), whose sum is σ = 5208000. Its totient is φ = 400896.

The previous prime is 1591417. The next prime is 1591441. The reversal of 1591440 is 441951.

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 (24).

It is a nialpdrome in base 11.

It is a zygodrome in base 11.

It is a self number, because there is not a number n which added to its sum of digits gives 1591440.

It is not an unprimeable number, because it can be changed into a prime (1591441) 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, 4386 + ... + 4734.

It is an arithmetic number, because the mean of its divisors is an integer number (65100).

2^1591440 is an apocalyptic number.

1591440 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 1591440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2604000).

1591440 is an abundant number, since it is smaller than the sum of its proper divisors (3616560).

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

1591440 is a wasteful number, since it uses less digits than its factorization.

1591440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 384 (or 378 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 24.

The square root of 1591440 is about 1261.5228892097. The cubic root of 1591440 is about 116.7517565194.

The spelling of 1591440 in words is "one million, five hundred ninety-one thousand, four hundred forty".