210021221173 has 2 divisors, whose sum is σ = 210021221174. Its totient is φ = 210021221172.

The previous prime is 210021221083. The next prime is 210021221237. The reversal of 210021221173 is 371122120012.

210021221173 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 189310269604 + 20710951569 = 435098^2 + 143913^2 .

It is a cyclic number.

It is not a de Polignac number, because 210021221173 - 2¹⁷ = 210021090101 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (210021228173) 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, 105010610586 + 105010610587.

It is an arithmetic number, because the mean of its divisors is an integer number (105010610587).

Almost surely, 2^210021221173 is an apocalyptic number.

It is an amenable number.

210021221173 is a deficient number, since it is larger than the sum of its proper divisors (1).

210021221173 is an equidigital number, since it uses as much as digits as its factorization.

210021221173 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 336, while the sum is 22.

Adding to 210021221173 its reverse (371122120012), we get a palindrome (581143341185).

The spelling of 210021221173 in words is "two hundred ten billion, twenty-one million, two hundred twenty-one thousand, one hundred seventy-three".