25122666857 has 4 divisors (see below), whose sum is σ = 25132358100. Its totient is φ = 25112975616.

The previous prime is 25122666851. The next prime is 25122666917. The reversal of 25122666857 is 75866622152.

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 15121866841 + 10000800016 = 122971^2 + 100004^2 .

It is a cyclic number.

It is not a de Polignac number, because 25122666857 - 2²⁰ = 25121618281 is a prime.

It is a super-2 number, since 2×25122666857² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25122666851) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4841732 + ... + 4846917.

It is an arithmetic number, because the mean of its divisors is an integer number (6283089525).

Almost surely, 2^25122666857 is an apocalyptic number.

It is an amenable number.

25122666857 is a deficient number, since it is larger than the sum of its proper divisors (9691243).

25122666857 is an equidigital number, since it uses as much as digits as its factorization.

25122666857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9691242.

The product of its digits is 2419200, while the sum is 50.

The spelling of 25122666857 in words is "twenty-five billion, one hundred twenty-two million, six hundred sixty-six thousand, eight hundred fifty-seven".