2509540 has 72 divisors (see below), whose sum is σ = 6233976. Its totient is φ = 844800.

The previous prime is 2509537. The next prime is 2509541. The reversal of 2509540 is 459052.

It can be written as a sum of positive squares in 4 ways, for example, as 69696 + 2439844 = 264^2 + 1562^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2509541) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 41110 + ... + 41170.

It is an arithmetic number, because the mean of its divisors is an integer number (86583).

2^2509540 is an apocalyptic number.

2509540 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 2509540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3116988).

2509540 is an abundant number, since it is smaller than the sum of its proper divisors (3724436).

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

2509540 is a wasteful number, since it uses less digits than its factorization.

2509540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109 (or 96 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 2509540 is about 1584.1527704107. The cubic root of 2509540 is about 135.8932986603.

The spelling of 2509540 in words is "two million, five hundred nine thousand, five hundred forty".