25820872771 has 4 divisors (see below), whose sum is σ = 25821926712. Its totient is φ = 25819818832.

The previous prime is 25820872751. The next prime is 25820872801. The reversal of 25820872771 is 17727802852.

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 25820872771 - 2¹⁷ = 25820741699 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25820872711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 489325 + ... + 539518.

It is an arithmetic number, because the mean of its divisors is an integer number (6455481678).

Almost surely, 2^25820872771 is an apocalyptic number.

25820872771 is a deficient number, since it is larger than the sum of its proper divisors (1053941).

25820872771 is a wasteful number, since it uses less digits than its factorization.

25820872771 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1053940.

The product of its (nonzero) digits is 878080, while the sum is 49.

The spelling of 25820872771 in words is "twenty-five billion, eight hundred twenty million, eight hundred seventy-two thousand, seven hundred seventy-one".