2561726553 has 8 divisors (see below), whose sum is σ = 3430683168. Its totient is φ = 1700293824.

The previous prime is 2561726533. The next prime is 2561726579. The reversal of 2561726553 is 3556271652.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 2561726553 - 2¹³ = 2561718361 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2561726533) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1880176 + ... + 1881537.

It is an arithmetic number, because the mean of its divisors is an integer number (428835396).

Almost surely, 2^2561726553 is an apocalyptic number.

It is an amenable number.

2561726553 is a deficient number, since it is larger than the sum of its proper divisors (868956615).

2561726553 is a wasteful number, since it uses less digits than its factorization.

2561726553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3761943.

The product of its digits is 378000, while the sum is 42.

The square root of 2561726553 is about 50613.5016868029. The cubic root of 2561726553 is about 1368.2882261563.

The spelling of 2561726553 in words is "two billion, five hundred sixty-one million, seven hundred twenty-six thousand, five hundred fifty-three".