12123321013 has 4 divisors (see below), whose sum is σ = 12761390560. Its totient is φ = 11485251468.

The previous prime is 12123320983. The next prime is 12123321017. The reversal of 12123321013 is 31012332121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 12123321013 - 2⁹ = 12123320501 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19), and also a Moran number because the ratio is a prime number: 638069527 = 12123321013 / (1 + 2 + 1 + 2 + 3 + 3 + 2 + 1 + 0 + 1 + 3).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12123321017) 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, 319034745 + ... + 319034782.

It is an arithmetic number, because the mean of its divisors is an integer number (3190347640).

Almost surely, 2^12123321013 is an apocalyptic number.

It is an amenable number.

12123321013 is a deficient number, since it is larger than the sum of its proper divisors (638069547).

12123321013 is an equidigital number, since it uses as much as digits as its factorization.

12123321013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 638069546.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 12123321013 its reverse (31012332121), we get a palindrome (43135653134).

It can be divided in two parts, 12 and 123321013, that added together give a square (123321025 = 11105²).

The spelling of 12123321013 in words is "twelve billion, one hundred twenty-three million, three hundred twenty-one thousand, thirteen".