2505640 has 32 divisors (see below), whose sum is σ = 5793480. Its totient is φ = 974592.

The previous prime is 2505631. The next prime is 2505641. The reversal of 2505640 is 465052.

2505640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 2292196 + 213444 = 1514^2 + 462^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2505641) 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, 634 + ... + 2326.

2^2505640 is an apocalyptic number.

2505640 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 2505640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2896740).

2505640 is an abundant number, since it is smaller than the sum of its proper divisors (3287840).

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

2505640 is a wasteful number, since it uses less digits than its factorization.

2505640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1741 (or 1737 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 22.

The square root of 2505640 is about 1582.9213499097. The cubic root of 2505640 is about 135.8228662775.

The spelling of 2505640 in words is "two million, five hundred five thousand, six hundred forty".