21902100173 has 2 divisors, whose sum is σ = 21902100174. Its totient is φ = 21902100172.

The previous prime is 21902100167. The next prime is 21902100257. The reversal of 21902100173 is 37100120912.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16439855524 + 5462244649 = 128218^2 + 73907^2 .

It is a cyclic number.

It is not a de Polignac number, because 21902100173 - 2⁸ = 21902099917 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21902100373) 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, 10951050086 + 10951050087.

It is an arithmetic number, because the mean of its divisors is an integer number (10951050087).

Almost surely, 2^21902100173 is an apocalyptic number.

It is an amenable number.

21902100173 is a deficient number, since it is larger than the sum of its proper divisors (1).

21902100173 is an equidigital number, since it uses as much as digits as its factorization.

21902100173 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 756, while the sum is 26.

The spelling of 21902100173 in words is "twenty-one billion, nine hundred two million, one hundred thousand, one hundred seventy-three".