25717818457 has 4 divisors (see below), whose sum is σ = 26547425536. Its totient is φ = 24888211380.

The previous prime is 25717818449. The next prime is 25717818521. The reversal of 25717818457 is 75481871752.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 25717818457 - 2³ = 25717818449 is a prime.

It is a super-2 number, since 2×25717818457² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 25717818398 and 25717818407.

It is not an unprimeable number, because it can be changed into a prime (25717818757) 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, 414803493 + ... + 414803554.

It is an arithmetic number, because the mean of its divisors is an integer number (6636856384).

Almost surely, 2^25717818457 is an apocalyptic number.

It is an amenable number.

25717818457 is a deficient number, since it is larger than the sum of its proper divisors (829607079).

25717818457 is an equidigital number, since it uses as much as digits as its factorization.

25717818457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 829607078.

The product of its digits is 4390400, while the sum is 55.

The spelling of 25717818457 in words is "twenty-five billion, seven hundred seventeen million, eight hundred eighteen thousand, four hundred fifty-seven".