25518865 has 4 divisors (see below), whose sum is σ = 30622644. Its totient is φ = 20415088.

The previous prime is 25518841. The next prime is 25518877. The reversal of 25518865 is 56881552.

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 10246401 + 15272464 = 3201^2 + 3908^2 .

It is a cyclic number.

It is not a de Polignac number, because 25518865 - 2²³ = 17130257 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, 2551882 + ... + 2551891.

It is an arithmetic number, because the mean of its divisors is an integer number (7655661).

Almost surely, 2^25518865 is an apocalyptic number.

It is an amenable number.

25518865 is a deficient number, since it is larger than the sum of its proper divisors (5103779).

25518865 is an equidigital number, since it uses as much as digits as its factorization.

25518865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5103778.

The product of its digits is 96000, while the sum is 40.

The square root of 25518865 is about 5051.6200371762. The cubic root of 25518865 is about 294.4108321533.

The spelling of 25518865 in words is "twenty-five million, five hundred eighteen thousand, eight hundred sixty-five".