25849099865 has 4 divisors (see below), whose sum is σ = 31018919844. Its totient is φ = 20679279888.

The previous prime is 25849099849. The next prime is 25849099873. The reversal of 25849099865 is 56899094852.

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 19438215241 + 6410884624 = 139421^2 + 80068^2 .

It is a cyclic number.

It is not a de Polignac number, because 25849099865 - 2⁴ = 25849099849 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2584909982 + ... + 2584909991.

It is an arithmetic number, because the mean of its divisors is an integer number (7754729961).

Almost surely, 2^25849099865 is an apocalyptic number.

It is an amenable number.

25849099865 is a deficient number, since it is larger than the sum of its proper divisors (5169819979).

25849099865 is an equidigital number, since it uses as much as digits as its factorization.

25849099865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5169819978.

The product of its (nonzero) digits is 55987200, while the sum is 65.

The spelling of 25849099865 in words is "twenty-five billion, eight hundred forty-nine million, ninety-nine thousand, eight hundred sixty-five".