2561040 has 60 divisors (see below), whose sum is σ = 8603244. Its totient is φ = 682752.

The previous prime is 2561023. The next prime is 2561051. The reversal of 2561040 is 401652.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 589824 + 1971216 = 768^2 + 1404^2 .

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an Ulam number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1059 + ... + 2498.

2^2561040 is an apocalyptic number.

2561040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2561040 is an abundant number, since it is smaller than the sum of its proper divisors (6042204).

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

2561040 is a wasteful number, since it uses less digits than its factorization.

2561040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3576 (or 3567 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 2561040 is about 1600.3249669989. The cubic root of 2561040 is about 136.8165979656.

Adding to 2561040 its reverse (401652), we get a palindrome (2962692).

It can be divided in two parts, 256 and 1040, that added together give a 4-th power (1296 = 6⁴).

The spelling of 2561040 in words is "two million, five hundred sixty-one thousand, forty".