21210220210073 has 2 divisors, whose sum is σ = 21210220210074. Its totient is φ = 21210220210072.

The previous prime is 21210220210007. The next prime is 21210220210163. The reversal of 21210220210073 is 37001202201212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14056590620944 + 7153629589129 = 3749212^2 + 2674627^2 .

It is a cyclic number.

It is not a de Polignac number, because 21210220210073 - 2⁸ = 21210220209817 is a prime.

It is not a weakly prime, because it can be changed into another prime (21210220215073) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605110105036 + 10605110105037.

It is an arithmetic number, because the mean of its divisors is an integer number (10605110105037).

Almost surely, 2^{21210220210073} is an apocalyptic number.

It is an amenable number.

21210220210073 is a deficient number, since it is larger than the sum of its proper divisors (1).

21210220210073 is an equidigital number, since it uses as much as digits as its factorization.

21210220210073 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 672, while the sum is 23.

Adding to 21210220210073 its reverse (37001202201212), we get a palindrome (58211422411285).

The spelling of 21210220210073 in words is "twenty-one trillion, two hundred ten billion, two hundred twenty million, two hundred ten thousand, seventy-three".