2521440 has 144 divisors (see below), whose sum is σ = 9199008. Its totient is φ = 626688.

The previous prime is 2521429. The next prime is 2521451. The reversal of 2521440 is 441252.

It is an interprime number because it is at equal distance from previous prime (2521429) and next prime (2521451).

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 24429 + ... + 24531.

It is an arithmetic number, because the mean of its divisors is an integer number (63882).

2^2521440 is an apocalyptic number.

2521440 is a gapful number since it is divisible by the number (20) 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 2521440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4599504).

2521440 is an abundant number, since it is smaller than the sum of its proper divisors (6677568).

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

2521440 is a wasteful number, since it uses less digits than its factorization.

2521440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 141 (or 130 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 2521440 is about 1587.9042792310. The cubic root of 2521440 is about 136.1077577343.

Adding to 2521440 its reverse (441252), we get a palindrome (2962692).

The spelling of 2521440 in words is "two million, five hundred twenty-one thousand, four hundred forty".