2561831613 has 12 divisors (see below), whose sum is σ = 4036825728. Its totient is φ = 1552625160.

The previous prime is 2561831611. The next prime is 2561831633. The reversal of 2561831613 is 3161381652.

2561831613 is a `hidden beast` number, since 2 + 5 + 6 + 1 + 8 + 31 + 613 = 666.

It is not a de Polignac number, because 2561831613 - 2¹ = 2561831611 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2561831611) 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 11 ways as a sum of consecutive naturals, for example, 12938445 + ... + 12938642.

It is an arithmetic number, because the mean of its divisors is an integer number (336402144).

Almost surely, 2^2561831613 is an apocalyptic number.

It is an amenable number.

2561831613 is a deficient number, since it is larger than the sum of its proper divisors (1474994115).

2561831613 is a wasteful number, since it uses less digits than its factorization.

2561831613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25877104 (or 25877101 counting only the distinct ones).

The product of its digits is 25920, while the sum is 36.

The square root of 2561831613 is about 50614.5395415191. The cubic root of 2561831613 is about 1368.3069310406.

The spelling of 2561831613 in words is "two billion, five hundred sixty-one million, eight hundred thirty-one thousand, six hundred thirteen".