2561040105625 has 15 divisors (see below), whose sum is σ = 3200325710923. Its totient is φ = 2048800078000.

The previous prime is 2561040105623. The next prime is 2561040105641. The reversal of 2561040105625 is 5265010401652.

The square root of 2561040105625 is 1600325.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 7 ways, for example, as 223089016329 + 2337951089296 = 472323^2 + 1529036^2 .

It is not a de Polignac number, because 2561040105625 - 2¹ = 2561040105623 is a prime.

It is a super-2 number, since 2×2561040105625² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2561040105623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 39976119 + ... + 40040131.

Almost surely, 2^{2561040105625} is an apocalyptic number.

2561040105625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

2561040105625 is the 1600325-th square number.

2561040105625 is the 800163-rd centered octagonal number.

It is an amenable number.

2561040105625 is a deficient number, since it is larger than the sum of its proper divisors (639285605298).

2561040105625 is an frugal number, since it uses more digits than its factorization.

2561040105625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128046 (or 64018 counting only the distinct ones).

The product of its (nonzero) digits is 72000, while the sum is 37.

The spelling of 2561040105625 in words is "two trillion, five hundred sixty-one billion, forty million, one hundred five thousand, six hundred twenty-five".