13121365123 has 4 divisors (see below), whose sum is σ = 13162757760. Its totient is φ = 13079972488.

The previous prime is 13121365111. The next prime is 13121365181. The reversal of 13121365123 is 32156312131.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32156312131 = 8741 ⋅3678791.

It is a cyclic number.

It is not a de Polignac number, because 13121365123 - 2²¹ = 13119267971 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 13121365091 and 13121365100.

It is not an unprimeable number, because it can be changed into a prime (13121365193) 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, 20695843 + ... + 20696476.

It is an arithmetic number, because the mean of its divisors is an integer number (3290689440).

Almost surely, 2^13121365123 is an apocalyptic number.

13121365123 is a deficient number, since it is larger than the sum of its proper divisors (41392637).

13121365123 is an equidigital number, since it uses as much as digits as its factorization.

13121365123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41392636.

The product of its digits is 3240, while the sum is 28.

Adding to 13121365123 its reverse (32156312131), we get a palindrome (45277677254).

The spelling of 13121365123 in words is "thirteen billion, one hundred twenty-one million, three hundred sixty-five thousand, one hundred twenty-three".