210105042420421 has 2 divisors, whose sum is σ = 210105042420422. Its totient is φ = 210105042420420.

The previous prime is 210105042420419. The next prime is 210105042420439. The reversal of 210105042420421 is 124024240501012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 124583792447521 + 85521249972900 = 11161711^2 + 9247770^2 .

It is a cyclic number.

It is not a de Polignac number, because 210105042420421 - 2¹ = 210105042420419 is a prime.

Together with 210105042420419, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 210105042420421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (210105042420491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105052521210210 + 105052521210211.

It is an arithmetic number, because the mean of its divisors is an integer number (105052521210211).

Almost surely, 2^{210105042420421} is an apocalyptic number.

It is an amenable number.

210105042420421 is a deficient number, since it is larger than the sum of its proper divisors (1).

210105042420421 is an equidigital number, since it uses as much as digits as its factorization.

210105042420421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5120, while the sum is 28.

Adding to 210105042420421 its reverse (124024240501012), we get a palindrome (334129282921433).

The spelling of 210105042420421 in words is "two hundred ten trillion, one hundred five billion, forty-two million, four hundred twenty thousand, four hundred twenty-one".