26205458561 has 2 divisors, whose sum is σ = 26205458562. Its totient is φ = 26205458560.

The previous prime is 26205458527. The next prime is 26205458621. The reversal of 26205458561 is 16585450262.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26205458161 + 400 = 161881^2 + 20^2 .

It is a cyclic number.

It is not a de Polignac number, because 26205458561 - 2⁶ = 26205458497 is a prime.

It is not a weakly prime, because it can be changed into another prime (26205452561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13102729280 + 13102729281.

It is an arithmetic number, because the mean of its divisors is an integer number (13102729281).

Almost surely, 2^26205458561 is an apocalyptic number.

It is an amenable number.

26205458561 is a deficient number, since it is larger than the sum of its proper divisors (1).

26205458561 is an equidigital number, since it uses as much as digits as its factorization.

26205458561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576000, while the sum is 44.

The spelling of 26205458561 in words is "twenty-six billion, two hundred five million, four hundred fifty-eight thousand, five hundred sixty-one".