2400040 has 32 divisors (see below), whose sum is σ = 5589000. Its totient is φ = 926464.

The previous prime is 2400037. The next prime is 2400053. The reversal of 2400040 is 400042.

It can be written as a sum of positive squares in 4 ways, for example, as 1542564 + 857476 = 1242^2 + 926^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

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, 126 + ... + 2194.

2^2400040 is an apocalyptic number.

2400040 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 2400040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2794500).

2400040 is an abundant number, since it is smaller than the sum of its proper divisors (3188960).

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

2400040 is a wasteful number, since it uses less digits than its factorization.

2400040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2109 (or 2105 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 10.

The square root of 2400040 is about 1549.2062483737. The cubic root of 2400040 is about 133.8873338267.

Adding to 2400040 its reverse (400042), we get a palindrome (2800082).

The spelling of 2400040 in words is "two million, four hundred thousand, forty".