25866488897 has 4 divisors (see below), whose sum is σ = 26758436820. Its totient is φ = 24974540976.

The previous prime is 25866488891. The next prime is 25866488899. The reversal of 25866488897 is 79888466852.

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

It can be written as a sum of positive squares in 2 ways, for example, as 22021372816 + 3845116081 = 148396^2 + 62009^2 .

It is a cyclic number.

It is not a de Polignac number, because 25866488897 - 2⁴ = 25866488881 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 25866488897.

It is not an unprimeable number, because it can be changed into a prime (25866488891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 445973918 + ... + 445973975.

It is an arithmetic number, because the mean of its divisors is an integer number (6689609205).

Almost surely, 2^25866488897 is an apocalyptic number.

It is an amenable number.

25866488897 is a deficient number, since it is larger than the sum of its proper divisors (891947923).

25866488897 is an equidigital number, since it uses as much as digits as its factorization.

25866488897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 891947922.

The product of its digits is 371589120, while the sum is 71.

The spelling of 25866488897 in words is "twenty-five billion, eight hundred sixty-six million, four hundred eighty-eight thousand, eight hundred ninety-seven".