25521121 has 4 divisors (see below), whose sum is σ = 25546500. Its totient is φ = 25495744.

The previous prime is 25521113. The next prime is 25521127. The reversal of 25521121 is 12112552.

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 21986721 + 3534400 = 4689^2 + 1880^2 .

It is a cyclic number.

It is not a de Polignac number, because 25521121 - 2³ = 25521113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25521127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11116 + ... + 13213.

It is an arithmetic number, because the mean of its divisors is an integer number (6386625).

Almost surely, 2^25521121 is an apocalyptic number.

It is an amenable number.

25521121 is a deficient number, since it is larger than the sum of its proper divisors (25379).

25521121 is a wasteful number, since it uses less digits than its factorization.

25521121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25378.

The product of its digits is 200, while the sum is 19.

The square root of 25521121 is about 5051.8433269451. The cubic root of 25521121 is about 294.4195077124.

Adding to 25521121 its reverse (12112552), we get a palindrome (37633673).

The spelling of 25521121 in words is "twenty-five million, five hundred twenty-one thousand, one hundred twenty-one".