2561326376251 has 2 divisors, whose sum is σ = 2561326376252. Its totient is φ = 2561326376250.

The previous prime is 2561326376237. The next prime is 2561326376263. The reversal of 2561326376251 is 1526736231652.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2561326376251 - 2⁹ = 2561326375739 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2561326376195 and 2561326376204.

It is not a weakly prime, because it can be changed into another prime (2561326376291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1280663188125 + 1280663188126.

It is an arithmetic number, because the mean of its divisors is an integer number (1280663188126).

Almost surely, 2^{2561326376251} is an apocalyptic number.

2561326376251 is a deficient number, since it is larger than the sum of its proper divisors (1).

2561326376251 is an equidigital number, since it uses as much as digits as its factorization.

2561326376251 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2721600, while the sum is 49.

The spelling of 2561326376251 in words is "two trillion, five hundred sixty-one billion, three hundred twenty-six million, three hundred seventy-six thousand, two hundred fifty-one".