25865217 has 32 divisors (see below), whose sum is σ = 44236800. Its totient is φ = 14630544.

The previous prime is 25865209. The next prime is 25865263. The reversal of 25865217 is 71256852.

It is a happy number.

It is not a de Polignac number, because 25865217 - 2³ = 25865209 is a prime.

It is a super-3 number, since 3×25865217³ (a number of 23 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (25865017) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 19584 + ... + 20862.

It is an arithmetic number, because the mean of its divisors is an integer number (1382400).

Almost surely, 2^25865217 is an apocalyptic number.

25865217 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

25865217 is a deficient number, since it is larger than the sum of its proper divisors (18371583).

25865217 is a wasteful number, since it uses less digits than its factorization.

25865217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1402 (or 1396 counting only the distinct ones).

The product of its digits is 33600, while the sum is 36.

The square root of 25865217 is about 5085.7857799951. The cubic root of 25865217 is about 295.7368041783.

The spelling of 25865217 in words is "twenty-five million, eight hundred sixty-five thousand, two hundred seventeen".