25217215 has 4 divisors (see below), whose sum is σ = 30260664. Its totient is φ = 20173768.

The previous prime is 25217201. The next prime is 25217233. The reversal of 25217215 is 51271252.

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 25217215 - 2¹⁵ = 25184447 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 25217215.

It is a congruent 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, 2521717 + ... + 2521726.

It is an arithmetic number, because the mean of its divisors is an integer number (7565166).

Almost surely, 2^25217215 is an apocalyptic number.

25217215 is a deficient number, since it is larger than the sum of its proper divisors (5043449).

25217215 is an equidigital number, since it uses as much as digits as its factorization.

25217215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5043448.

The product of its digits is 1400, while the sum is 25.

The square root of 25217215 is about 5021.6745215117. The cubic root of 25217215 is about 293.2461869509.

Adding to 25217215 its reverse (51271252), we get a palindrome (76488467).

The spelling of 25217215 in words is "twenty-five million, two hundred seventeen thousand, two hundred fifteen".