2605656023261 has 2 divisors, whose sum is σ = 2605656023262. Its totient is φ = 2605656023260.

The previous prime is 2605656023227. The next prime is 2605656023263. The reversal of 2605656023261 is 1623206565062.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1565266223236 + 1040389800025 = 1251106^2 + 1019995^2 .

It is a cyclic number.

It is not a de Polignac number, because 2605656023261 - 2⁶ = 2605656023197 is a prime.

Together with 2605656023263, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2605656023263) 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, 1302828011630 + 1302828011631.

It is an arithmetic number, because the mean of its divisors is an integer number (1302828011631).

Almost surely, 2^{2605656023261} is an apocalyptic number.

It is an amenable number.

2605656023261 is a deficient number, since it is larger than the sum of its proper divisors (1).

2605656023261 is an equidigital number, since it uses as much as digits as its factorization.

2605656023261 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 777600, while the sum is 44.

It can be divided in two parts, 260565 and 6023261, that added together give a palindrome (6283826).

The spelling of 2605656023261 in words is "two trillion, six hundred five billion, six hundred fifty-six million, twenty-three thousand, two hundred sixty-one".