25521017 has 4 divisors (see below), whose sum is σ = 25807860. Its totient is φ = 25234176.

The previous prime is 25521011. The next prime is 25521043. The reversal of 25521017 is 71012552.

It is a happy number.

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 2298256 + 23222761 = 1516^2 + 4819^2 .

It is a cyclic number.

It is not a de Polignac number, because 25521017 - 2¹⁰ = 25519993 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 25520983 and 25521001.

It is not an unprimeable number, because it can be changed into a prime (25521011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 143288 + ... + 143465.

It is an arithmetic number, because the mean of its divisors is an integer number (6451965).

Almost surely, 2^25521017 is an apocalyptic number.

It is an amenable number.

25521017 is a deficient number, since it is larger than the sum of its proper divisors (286843).

25521017 is an equidigital number, since it uses as much as digits as its factorization.

25521017 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 286842.

The product of its (nonzero) digits is 700, while the sum is 23.

The square root of 25521017 is about 5051.8330336621. The cubic root of 25521017 is about 294.4191077865.

Adding to 25521017 its reverse (71012552), we get a palindrome (96533569).

The spelling of 25521017 in words is "twenty-five million, five hundred twenty-one thousand, seventeen".