21675423173 has 2 divisors, whose sum is σ = 21675423174. Its totient is φ = 21675423172.

The previous prime is 21675423167. The next prime is 21675423179. The reversal of 21675423173 is 37132457612.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (21675423167) and next prime (21675423179).

It can be written as a sum of positive squares in only one way, i.e., 20907135649 + 768287524 = 144593^2 + 27718^2 .

It is a cyclic number.

It is not a de Polignac number, because 21675423173 - 2⁴ = 21675423157 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21675423173.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21675423179) 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, 10837711586 + 10837711587.

It is an arithmetic number, because the mean of its divisors is an integer number (10837711587).

Almost surely, 2^21675423173 is an apocalyptic number.

It is an amenable number.

21675423173 is a deficient number, since it is larger than the sum of its proper divisors (1).

21675423173 is an equidigital number, since it uses as much as digits as its factorization.

21675423173 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 211680, while the sum is 41.

The spelling of 21675423173 in words is "twenty-one billion, six hundred seventy-five million, four hundred twenty-three thousand, one hundred seventy-three".