2543840 has 48 divisors (see below), whose sum is σ = 6477408. Its totient is φ = 938496.

The previous prime is 2543833. The next prime is 2543843. The reversal of 2543840 is 483452.

It is a super-2 number, since 2×2543840² = 12942243891200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (26).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2543843) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1469 + ... + 2691.

It is an arithmetic number, because the mean of its divisors is an integer number (134946).

2^2543840 is an apocalyptic number.

2543840 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 2543840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3238704).

2543840 is an abundant number, since it is smaller than the sum of its proper divisors (3933568).

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

2543840 is a wasteful number, since it uses less digits than its factorization.

2543840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1251 (or 1243 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 26.

The square root of 2543840 is about 1594.9420052152. The cubic root of 2543840 is about 136.5096219742.

The spelling of 2543840 in words is "two million, five hundred forty-three thousand, eight hundred forty".