13123113121 has 4 divisors (see below), whose sum is σ = 13477791892. Its totient is φ = 12768434352.

The previous prime is 13123113079. The next prime is 13123113137. The reversal of 13123113121 is 12131132131.

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 10464267025 + 2658846096 = 102295^2 + 51564^2 .

It is a cyclic number.

It is not a de Polignac number, because 13123113121 - 2⁹ = 13123112609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13123113181) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 177339330 + ... + 177339403.

It is an arithmetic number, because the mean of its divisors is an integer number (3369447973).

Almost surely, 2^13123113121 is an apocalyptic number.

It is an amenable number.

13123113121 is a deficient number, since it is larger than the sum of its proper divisors (354678771).

13123113121 is an equidigital number, since it uses as much as digits as its factorization.

13123113121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 354678770.

The product of its digits is 108, while the sum is 19.

Adding to 13123113121 its reverse (12131132131), we get a palindrome (25254245252).

The spelling of 13123113121 in words is "thirteen billion, one hundred twenty-three million, one hundred thirteen thousand, one hundred twenty-one".