2561304641 has 4 divisors (see below), whose sum is σ = 2927205312. Its totient is φ = 2195403972.

The previous prime is 2561304611. The next prime is 2561304667. The reversal of 2561304641 is 1464031652.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2561304641 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2561304598 and 2561304607.

It is not an unprimeable number, because it can be changed into a prime (2561304611) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 182950325 + ... + 182950338.

It is an arithmetic number, because the mean of its divisors is an integer number (731801328).

Almost surely, 2^2561304641 is an apocalyptic number.

It is an amenable number.

2561304641 is a deficient number, since it is larger than the sum of its proper divisors (365900671).

2561304641 is an equidigital number, since it uses as much as digits as its factorization.

2561304641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 365900670.

The product of its (nonzero) digits is 17280, while the sum is 32.

The square root of 2561304641 is about 50609.3335364140. Note that the first 3 decimals coincide. The cubic root of 2561304641 is about 1368.2131037852.

The spelling of 2561304641 in words is "two billion, five hundred sixty-one million, three hundred four thousand, six hundred forty-one".