21200102173 has 2 divisors, whose sum is σ = 21200102174. Its totient is φ = 21200102172.

The previous prime is 21200102159. The next prime is 21200102191. The reversal of 21200102173 is 37120100212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13769144964 + 7430957209 = 117342^2 + 86203^2 .

It is a cyclic number.

It is not a de Polignac number, because 21200102173 - 2⁹ = 21200101661 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21200102173.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21200109173) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600051086 + 10600051087.

It is an arithmetic number, because the mean of its divisors is an integer number (10600051087).

Almost surely, 2^21200102173 is an apocalyptic number.

It is an amenable number.

21200102173 is a deficient number, since it is larger than the sum of its proper divisors (1).

21200102173 is an equidigital number, since it uses as much as digits as its factorization.

21200102173 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 21200102173 its reverse (37120100212), we get a palindrome (58320202385).

The spelling of 21200102173 in words is "twenty-one billion, two hundred million, one hundred two thousand, one hundred seventy-three".