25516548121 has 3 divisors (see below), whose sum is σ = 25516707861. Its totient is φ = 25516388382.

The previous prime is 25516548107. The next prime is 25516548143. The reversal of 25516548121 is 12184561552.

The square root of 25516548121 is 159739.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 25516548121 - 2⁷ = 25516547993 is a prime.

It is a super-2 number, since 2×25516548121² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25516548181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 79870 + ... + 239608.

It is an arithmetic number, because the mean of its divisors is an integer number (8505569287).

Almost surely, 2^25516548121 is an apocalyptic number.

25516548121 is the 159739-th square number.

25516548121 is the 79870-th centered octagonal number.

It is an amenable number.

25516548121 is a deficient number, since it is larger than the sum of its proper divisors (159740).

25516548121 is an frugal number, since it uses more digits than its factorization.

25516548121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 319478 (or 159739 counting only the distinct ones).

The product of its digits is 96000, while the sum is 40.

The spelling of 25516548121 in words is "twenty-five billion, five hundred sixteen million, five hundred forty-eight thousand, one hundred twenty-one".