217122784493 has 2 divisors, whose sum is σ = 217122784494. Its totient is φ = 217122784492.

The previous prime is 217122784471. The next prime is 217122784507. The reversal of 217122784493 is 394487221712.

217122784493 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., 213834106084 + 3288678409 = 462422^2 + 57347^2 .

It is a cyclic number.

It is not a de Polignac number, because 217122784493 - 2¹² = 217122780397 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (217122784453) 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, 108561392246 + 108561392247.

It is an arithmetic number, because the mean of its divisors is an integer number (108561392247).

Almost surely, 2^217122784493 is an apocalyptic number.

It is an amenable number.

217122784493 is a deficient number, since it is larger than the sum of its proper divisors (1).

217122784493 is an equidigital number, since it uses as much as digits as its factorization.

217122784493 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1354752, while the sum is 50.

The spelling of 217122784493 in words is "two hundred seventeen billion, one hundred twenty-two million, seven hundred eighty-four thousand, four hundred ninety-three".