2551440 has 40 divisors (see below), whose sum is σ = 7910208. Its totient is φ = 680320.

The previous prime is 2551433. The next prime is 2551441. The reversal of 2551440 is 441552.

2551440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a hoax number, since the sum of its digits (21) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (2551441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5076 + ... + 5555.

2^2551440 is an apocalyptic number.

2551440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2551440 is an abundant number, since it is smaller than the sum of its proper divisors (5358768).

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

2551440 is a wasteful number, since it uses less digits than its factorization.

2551440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10647 (or 10641 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 21.

The square root of 2551440 is about 1597.3227601208. The cubic root of 2551440 is about 136.6454326188.

Adding to 2551440 its reverse (441552), we get a palindrome (2992992).

The spelling of 2551440 in words is "two million, five hundred fifty-one thousand, four hundred forty".