2561240 has 32 divisors (see below), whose sum is σ = 6287760. Its totient is φ = 931200.

The previous prime is 2561239. The next prime is 2561261. The reversal of 2561240 is 421652.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20).

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, 2471 + ... + 3350.

2^2561240 is an apocalyptic number.

2561240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2561240 is an abundant number, since it is smaller than the sum of its proper divisors (3726520).

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

2561240 is a wasteful number, since it uses less digits than its factorization.

2561240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5843 (or 5839 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 2561240 is about 1600.3874530875. The cubic root of 2561240 is about 136.8201593582.

Adding to 2561240 its reverse (421652), we get a palindrome (2982892).

It can be divided in two parts, 25612 and 40, that added together give a palindrome (25652).

The spelling of 2561240 in words is "two million, five hundred sixty-one thousand, two hundred forty".