26345640257 has 2 divisors, whose sum is σ = 26345640258. Its totient is φ = 26345640256.

The previous prime is 26345640193. The next prime is 26345640281. The reversal of 26345640257 is 75204654362.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25972223281 + 373416976 = 161159^2 + 19324^2 .

It is a cyclic number.

It is not a de Polignac number, because 26345640257 - 2⁶ = 26345640193 is a prime.

It is not a weakly prime, because it can be changed into another prime (26345640157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13172820128 + 13172820129.

It is an arithmetic number, because the mean of its divisors is an integer number (13172820129).

Almost surely, 2^26345640257 is an apocalyptic number.

It is an amenable number.

26345640257 is a deficient number, since it is larger than the sum of its proper divisors (1).

26345640257 is an equidigital number, since it uses as much as digits as its factorization.

26345640257 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1209600, while the sum is 44.

The spelling of 26345640257 in words is "twenty-six billion, three hundred forty-five million, six hundred forty thousand, two hundred fifty-seven".