12545442121 has 2 divisors, whose sum is σ = 12545442122. Its totient is φ = 12545442120.

The previous prime is 12545442101. The next prime is 12545442131. The reversal of 12545442121 is 12124454521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10039038025 + 2506404096 = 100195^2 + 50064^2 .

It is a cyclic number.

It is not a de Polignac number, because 12545442121 - 2³³ = 3955507529 is a prime.

It is a super-3 number, since 3×12545442121³ (a number of 31 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (12545442101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6272721060 + 6272721061.

It is an arithmetic number, because the mean of its divisors is an integer number (6272721061).

Almost surely, 2^12545442121 is an apocalyptic number.

It is an amenable number.

12545442121 is a deficient number, since it is larger than the sum of its proper divisors (1).

12545442121 is an equidigital number, since it uses as much as digits as its factorization.

12545442121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12800, while the sum is 31.

Adding to 12545442121 its reverse (12124454521), we get a palindrome (24669896642).

The spelling of 12545442121 in words is "twelve billion, five hundred forty-five million, four hundred forty-two thousand, one hundred twenty-one".