26561425166663 has 4 divisors (see below), whose sum is σ = 26571961236288. Its totient is φ = 26550889097040.

The previous prime is 26561425166659. The next prime is 26561425166699. The reversal of 26561425166663 is 36666152416562.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 26561425166663 - 2² = 26561425166659 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (26561425166963) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5268031031 + ... + 5268036072.

It is an arithmetic number, because the mean of its divisors is an integer number (6642990309072).

Almost surely, 2^{26561425166663} is an apocalyptic number.

26561425166663 is a deficient number, since it is larger than the sum of its proper divisors (10536069625).

26561425166663 is a wasteful number, since it uses less digits than its factorization.

26561425166663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10536069624.

The product of its digits is 55987200, while the sum is 59.

The spelling of 26561425166663 in words is "twenty-six trillion, five hundred sixty-one billion, four hundred twenty-five million, one hundred sixty-six thousand, six hundred sixty-three".