25003521 has 12 divisors (see below), whose sum is σ = 36318100. Its totient is φ = 16575840.

The previous prime is 25003513. The next prime is 25003523. The reversal of 25003521 is 12530052.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 3101121 + 21902400 = 1761^2 + 4680^2 .

It is not a de Polignac number, because 25003521 - 2³ = 25003513 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 25003494 and 25003503.

It is not an unprimeable number, because it can be changed into a prime (25003523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6046 + ... + 9303.

Almost surely, 2^25003521 is an apocalyptic number.

It is an amenable number.

25003521 is a deficient number, since it is larger than the sum of its proper divisors (11314579).

25003521 is a wasteful number, since it uses less digits than its factorization.

25003521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15536 (or 15533 counting only the distinct ones).

The product of its (nonzero) digits is 300, while the sum is 18.

The square root of 25003521 is about 5000.3520876034. The cubic root of 25003521 is about 292.4155004655.

Adding to 25003521 its reverse (12530052), we get a palindrome (37533573).

The spelling of 25003521 in words is "twenty-five million, three thousand, five hundred twenty-one".