21010212073 has 2 divisors, whose sum is σ = 21010212074. Its totient is φ = 21010212072.

The previous prime is 21010212061. The next prime is 21010212133. The reversal of 21010212073 is 37021201012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20190420649 + 819791424 = 142093^2 + 28632^2 .

It is a cyclic number.

It is not a de Polignac number, because 21010212073 - 2⁹ = 21010211561 is a prime.

It is a super-2 number, since 2×21010212073² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21010212073.

It is not a weakly prime, because it can be changed into another prime (21010212473) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505106036 + 10505106037.

It is an arithmetic number, because the mean of its divisors is an integer number (10505106037).

Almost surely, 2^21010212073 is an apocalyptic number.

It is an amenable number.

21010212073 is a deficient number, since it is larger than the sum of its proper divisors (1).

21010212073 is an equidigital number, since it uses as much as digits as its factorization.

21010212073 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 168, while the sum is 19.

Adding to 21010212073 its reverse (37021201012), we get a palindrome (58031413085).

The spelling of 21010212073 in words is "twenty-one billion, ten million, two hundred twelve thousand, seventy-three".