2561345271 has 24 divisors (see below), whose sum is σ = 3849191424. Its totient is φ = 1639446480.

The previous prime is 2561345263. The next prime is 2561345321. The reversal of 2561345271 is 1725431652.

2561345271 is a `hidden beast` number, since 256 + 134 + 5 + 271 = 666.

It is not a de Polignac number, because 2561345271 - 2³ = 2561345263 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2561345231) 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 23 ways as a sum of consecutive naturals, for example, 711 + ... + 71576.

It is an arithmetic number, because the mean of its divisors is an integer number (160382976).

Almost surely, 2^2561345271 is an apocalyptic number.

2561345271 is a deficient number, since it is larger than the sum of its proper divisors (1287846153).

2561345271 is a wasteful number, since it uses less digits than its factorization.

2561345271 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72451 (or 72448 counting only the distinct ones).

The product of its digits is 50400, while the sum is 36.

The square root of 2561345271 is about 50609.7349429929. The cubic root of 2561345271 is about 1368.2203384061.

The spelling of 2561345271 in words is "two billion, five hundred sixty-one million, three hundred forty-five thousand, two hundred seventy-one".