2561231755 has 4 divisors (see below), whose sum is σ = 3073478112. Its totient is φ = 2048985400.

The previous prime is 2561231641. The next prime is 2561231759. The reversal of 2561231755 is 5571321652.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 2561231755 - 2⁹ = 2561231243 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2561231759) 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, 256123171 + ... + 256123180.

It is an arithmetic number, because the mean of its divisors is an integer number (768369528).

Almost surely, 2^2561231755 is an apocalyptic number.

2561231755 is a deficient number, since it is larger than the sum of its proper divisors (512246357).

2561231755 is an equidigital number, since it uses as much as digits as its factorization.

2561231755 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 512246356.

The product of its digits is 63000, while the sum is 37.

The square root of 2561231755 is about 50608.6134467247. The cubic root of 2561231755 is about 1368.2001254350.

The spelling of 2561231755 in words is "two billion, five hundred sixty-one million, two hundred thirty-one thousand, seven hundred fifty-five".