21200220009973 has 2 divisors, whose sum is σ = 21200220009974. Its totient is φ = 21200220009972.

The previous prime is 21200220009971. The next prime is 21200220010027. The reversal of 21200220009973 is 37990002200212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12809656167364 + 8390563842609 = 3579058^2 + 2896647^2 .

It is a cyclic number.

It is not a de Polignac number, because 21200220009973 - 2¹ = 21200220009971 is a prime.

Together with 21200220009971, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21200220009971) 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, 10600110004986 + 10600110004987.

It is an arithmetic number, because the mean of its divisors is an integer number (10600110004987).

Almost surely, 2^{21200220009973} is an apocalyptic number.

It is an amenable number.

21200220009973 is a deficient number, since it is larger than the sum of its proper divisors (1).

21200220009973 is an equidigital number, since it uses as much as digits as its factorization.

21200220009973 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27216, while the sum is 37.

The spelling of 21200220009973 in words is "twenty-one trillion, two hundred billion, two hundred twenty million, nine thousand, nine hundred seventy-three".