12420111421 has 2 divisors, whose sum is σ = 12420111422. Its totient is φ = 12420111420.

The previous prime is 12420111401. The next prime is 12420111499. The reversal of 12420111421 is 12411102421.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12190588921 + 229522500 = 110411^2 + 15150^2 .

It is a cyclic number.

It is not a de Polignac number, because 12420111421 - 2¹⁵ = 12420078653 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12420111401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6210055710 + 6210055711.

It is an arithmetic number, because the mean of its divisors is an integer number (6210055711).

Almost surely, 2^12420111421 is an apocalyptic number.

It is an amenable number.

12420111421 is a deficient number, since it is larger than the sum of its proper divisors (1).

12420111421 is an equidigital number, since it uses as much as digits as its factorization.

12420111421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 12420111421 its reverse (12411102421), we get a palindrome (24831213842).

The spelling of 12420111421 in words is "twelve billion, four hundred twenty million, one hundred eleven thousand, four hundred twenty-one".