12123119821 has 2 divisors, whose sum is σ = 12123119822. Its totient is φ = 12123119820.

The previous prime is 12123119797. The next prime is 12123119881. The reversal of 12123119821 is 12891132121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6303566025 + 5819553796 = 79395^2 + 76286^2 .

It is a cyclic number.

It is not a de Polignac number, because 12123119821 - 2¹³ = 12123111629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12123119881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6061559910 + 6061559911.

It is an arithmetic number, because the mean of its divisors is an integer number (6061559911).

Almost surely, 2^12123119821 is an apocalyptic number.

It is an amenable number.

12123119821 is a deficient number, since it is larger than the sum of its proper divisors (1).

12123119821 is an equidigital number, since it uses as much as digits as its factorization.

12123119821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1728, while the sum is 31.

The spelling of 12123119821 in words is "twelve billion, one hundred twenty-three million, one hundred nineteen thousand, eight hundred twenty-one".