25121025121 has 8 divisors (see below), whose sum is σ = 25373320488. Its totient is φ = 24868800000.

The previous prime is 25121025113. The next prime is 25121025131. The reversal of 25121025121 is 12152012152.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 16735044496 + 8385980625 = 129364^2 + 91575^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 25121025121 - 2³ = 25121025113 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 25121025092 and 25121025101.

It is not an unprimeable number, because it can be changed into a prime (25121025131) 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 7 ways as a sum of consecutive naturals, for example, 987441 + ... + 1012561.

It is an arithmetic number, because the mean of its divisors is an integer number (3171665061).

Almost surely, 2^25121025121 is an apocalyptic number.

It is an amenable number.

25121025121 is a deficient number, since it is larger than the sum of its proper divisors (252295367).

25121025121 is a wasteful number, since it uses less digits than its factorization.

25121025121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35123.

The product of its (nonzero) digits is 400, while the sum is 22.

Adding to 25121025121 its reverse (12152012152), we get a palindrome (37273037273).

The spelling of 25121025121 in words is "twenty-five billion, one hundred twenty-one million, twenty-five thousand, one hundred twenty-one".