21525012325 has 6 divisors (see below), whose sum is σ = 26691015314. Its totient is φ = 17220009840.

The previous prime is 21525012317. The next prime is 21525012329. The reversal of 21525012325 is 52321052512.

It can be written as a sum of positive squares in 3 ways, for example, as 5434343524 + 16090668801 = 73718^2 + 126849^2 .

It is not a de Polignac number, because 21525012325 - 2³ = 21525012317 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21525012293 and 21525012302.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21525012329) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 430500222 + ... + 430500271.

Almost surely, 2^21525012325 is an apocalyptic number.

21525012325 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21525012325 is a deficient number, since it is larger than the sum of its proper divisors (5166002989).

21525012325 is an equidigital number, since it uses as much as digits as its factorization.

21525012325 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 861000503 (or 861000498 counting only the distinct ones).

The product of its (nonzero) digits is 6000, while the sum is 28.

Adding to 21525012325 its reverse (52321052512), we get a palindrome (73846064837).

The spelling of 21525012325 in words is "twenty-one billion, five hundred twenty-five million, twelve thousand, three hundred twenty-five".