2561326361 has 16 divisors (see below), whose sum is σ = 2896777728. Its totient is φ = 2243625600.

The previous prime is 2561326357. The next prime is 2561326379. The reversal of 2561326361 is 1636231652.

2561326361 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 2561326361 - 2² = 2561326357 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2561326351) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 63335 + ... + 95571.

It is an arithmetic number, because the mean of its divisors is an integer number (181048608).

Almost surely, 2^2561326361 is an apocalyptic number.

It is an amenable number.

2561326361 is a deficient number, since it is larger than the sum of its proper divisors (335451367).

2561326361 is a wasteful number, since it uses less digits than its factorization.

2561326361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32512.

The product of its digits is 38880, while the sum is 35.

The square root of 2561326361 is about 50609.5481208833. The cubic root of 2561326361 is about 1368.2169712810.

The spelling of 2561326361 in words is "two billion, five hundred sixty-one million, three hundred twenty-six thousand, three hundred sixty-one".