25521005 has 4 divisors (see below), whose sum is σ = 30625212. Its totient is φ = 20416800.

The previous prime is 25520993. The next prime is 25521011. The reversal of 25521005 is 50012552.

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 3374569 + 22146436 = 1837^2 + 4706^2 .

It is not a de Polignac number, because 25521005 - 2⁸ = 25520749 is a prime.

It is a Duffinian number.

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, 2552096 + ... + 2552105.

It is an arithmetic number, because the mean of its divisors is an integer number (7656303).

Almost surely, 2^25521005 is an apocalyptic number.

It is an amenable number.

25521005 is a deficient number, since it is larger than the sum of its proper divisors (5104207).

25521005 is an equidigital number, since it uses as much as digits as its factorization.

25521005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5104206.

The product of its (nonzero) digits is 500, while the sum is 20.

The square root of 25521005 is about 5051.8318459743. The cubic root of 25521005 is about 294.4190616411.

Adding to 25521005 its reverse (50012552), we get a palindrome (75533557).

The spelling of 25521005 in words is "twenty-five million, five hundred twenty-one thousand, five".