25257216571 has 4 divisors (see below), whose sum is σ = 25493265432. Its totient is φ = 25021167712.

The previous prime is 25257216539. The next prime is 25257216577. The reversal of 25257216571 is 17561275252.

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 25257216571 - 2⁵ = 25257216539 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25257216577) 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, 118024270 + ... + 118024483.

It is an arithmetic number, because the mean of its divisors is an integer number (6373316358).

Almost surely, 2^25257216571 is an apocalyptic number.

25257216571 is a deficient number, since it is larger than the sum of its proper divisors (236048861).

25257216571 is a wasteful number, since it uses less digits than its factorization.

25257216571 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 236048860.

The product of its digits is 294000, while the sum is 43.

The spelling of 25257216571 in words is "twenty-five billion, two hundred fifty-seven million, two hundred sixteen thousand, five hundred seventy-one".