21227744173 has 2 divisors, whose sum is σ = 21227744174. Its totient is φ = 21227744172.

The previous prime is 21227744123. The next prime is 21227744207. The reversal of 21227744173 is 37144772212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20183032489 + 1044711684 = 142067^2 + 32322^2 .

It is a cyclic number.

It is not a de Polignac number, because 21227744173 - 2⁹ = 21227743661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21227744113) 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, 10613872086 + 10613872087.

It is an arithmetic number, because the mean of its divisors is an integer number (10613872087).

Almost surely, 2^21227744173 is an apocalyptic number.

It is an amenable number.

21227744173 is a deficient number, since it is larger than the sum of its proper divisors (1).

21227744173 is an equidigital number, since it uses as much as digits as its factorization.

21227744173 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 131712, while the sum is 40.

The spelling of 21227744173 in words is "twenty-one billion, two hundred twenty-seven million, seven hundred forty-four thousand, one hundred seventy-three".