21100223210173 has 2 divisors, whose sum is σ = 21100223210174. Its totient is φ = 21100223210172.

The previous prime is 21100223210161. The next prime is 21100223210267. The reversal of 21100223210173 is 37101232200112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13577913171684 + 7522310038489 = 3684822^2 + 2742683^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21100223210173 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21100223211173) 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, 10550111605086 + 10550111605087.

It is an arithmetic number, because the mean of its divisors is an integer number (10550111605087).

Almost surely, 2^{21100223210173} is an apocalyptic number.

It is an amenable number.

21100223210173 is a deficient number, since it is larger than the sum of its proper divisors (1).

21100223210173 is an equidigital number, since it uses as much as digits as its factorization.

21100223210173 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1008, while the sum is 25.

Adding to 21100223210173 its reverse (37101232200112), we get a palindrome (58201455410285).

The spelling of 21100223210173 in words is "twenty-one trillion, one hundred billion, two hundred twenty-three million, two hundred ten thousand, one hundred seventy-three".