12402420421 has 2 divisors, whose sum is σ = 12402420422. Its totient is φ = 12402420420.

The previous prime is 12402420413. The next prime is 12402420493.

12402420421 is nontrivially palindromic in base 10.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12329659521 + 72760900 = 111039^2 + 8530^2 .

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 12402420421 - 2³ = 12402420413 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12402420392 and 12402420401.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12402820421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6201210210 + 6201210211.

It is an arithmetic number, because the mean of its divisors is an integer number (6201210211).

Almost surely, 2^12402420421 is an apocalyptic number.

It is an amenable number.

12402420421 is a deficient number, since it is larger than the sum of its proper divisors (1).

12402420421 is an equidigital number, since it uses as much as digits as its factorization.

12402420421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1024, while the sum is 22.

The spelling of 12402420421 in words is "twelve billion, four hundred two million, four hundred twenty thousand, four hundred twenty-one".