2399440 has 40 divisors (see below), whose sum is σ = 5658120. Its totient is φ = 946176.

The previous prime is 2399407. The next prime is 2399461. The reversal of 2399440 is 449932.

It can be written as a sum of positive squares in 4 ways, for example, as 3136 + 2396304 = 56^2 + 1548^2 .

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6952 + ... + 7288.

It is an arithmetic number, because the mean of its divisors is an integer number (141453).

2^2399440 is an apocalyptic number.

2399440 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 2399440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2829060).

2399440 is an abundant number, since it is smaller than the sum of its proper divisors (3258680).

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

2399440 is a wasteful number, since it uses less digits than its factorization.

2399440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 439 (or 433 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 31.

The square root of 2399440 is about 1549.0125887158. The cubic root of 2399440 is about 133.8761758050.

The spelling of 2399440 in words is "two million, three hundred ninety-nine thousand, four hundred forty".