210421420042109 has 2 divisors, whose sum is σ = 210421420042110. Its totient is φ = 210421420042108.

The previous prime is 210421420042081. The next prime is 210421420042111. The reversal of 210421420042109 is 901240024124012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 130792960425625 + 79628459616484 = 11436475^2 + 8923478^2 .

It is a cyclic number.

It is not a de Polignac number, because 210421420042109 - 2⁴⁴ = 192829233997693 is a prime.

Together with 210421420042111, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (210421420042709) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105210710021054 + 105210710021055.

It is an arithmetic number, because the mean of its divisors is an integer number (105210710021055).

Almost surely, 2^{210421420042109} is an apocalyptic number.

It is an amenable number.

210421420042109 is a deficient number, since it is larger than the sum of its proper divisors (1).

210421420042109 is an equidigital number, since it uses as much as digits as its factorization.

210421420042109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9216, while the sum is 32.

The spelling of 210421420042109 in words is "two hundred ten trillion, four hundred twenty-one billion, four hundred twenty million, forty-two thousand, one hundred nine".