420130021 has 2 divisors, whose sum is σ = 420130022. Its totient is φ = 420130020.

The previous prime is 420130019. The next prime is 420130037. The reversal of 420130021 is 120031024.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 289850625 + 130279396 = 17025^2 + 11414^2 .

It is a cyclic number.

It is not a de Polignac number, because 420130021 - 2¹ = 420130019 is a prime.

Together with 420130019, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 420129983 and 420130010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (420130001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210065010 + 210065011.

It is an arithmetic number, because the mean of its divisors is an integer number (210065011).

Almost surely, 2^420130021 is an apocalyptic number.

It is an amenable number.

420130021 is a deficient number, since it is larger than the sum of its proper divisors (1).

420130021 is an equidigital number, since it uses as much as digits as its factorization.

420130021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 420130021 is about 20497.0734740353. The cubic root of 420130021 is about 748.9645093739.

Adding to 420130021 its reverse (120031024), we get a palindrome (540161045).

The spelling of 420130021 in words is "four hundred twenty million, one hundred thirty thousand, twenty-one".