2400840 has 192 divisors, whose sum is σ = 9172800. Its totient is φ = 559872.

The previous prime is 2400833. The next prime is 2400841. The reversal of 2400840 is 480042.

It is a happy number.

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

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2400841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 126351 + ... + 126369.

It is an arithmetic number, because the mean of its divisors is an integer number (47775).

2^2400840 is an apocalyptic number.

2400840 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 2400840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4586400).

2400840 is an abundant number, since it is smaller than the sum of its proper divisors (6771960).

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

2400840 is a wasteful number, since it uses less digits than its factorization.

2400840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58 (or 42 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 2400840 is about 1549.4644235993. The cubic root of 2400840 is about 133.9022082966.

Adding to 2400840 its reverse (480042), we get a palindrome (2880882).

It can be divided in two parts, 2400 and 840, that added together give a triangular number (3240 = T₈₀).

The spelling of 2400840 in words is "two million, four hundred thousand, eight hundred forty".