422173721 has 2 divisors, whose sum is σ = 422173722. Its totient is φ = 422173720.

The previous prime is 422173667. The next prime is 422173723. The reversal of 422173721 is 127371224.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 264420121 + 157753600 = 16261^2 + 12560^2 .

It is a cyclic number.

It is not a de Polignac number, because 422173721 - 2¹⁸ = 421911577 is a prime.

Together with 422173723, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (422173723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 211086860 + 211086861.

It is an arithmetic number, because the mean of its divisors is an integer number (211086861).

Almost surely, 2^422173721 is an apocalyptic number.

It is an amenable number.

422173721 is a deficient number, since it is larger than the sum of its proper divisors (1).

422173721 is an equidigital number, since it uses as much as digits as its factorization.

422173721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4704, while the sum is 29.

The square root of 422173721 is about 20546.8664520895. The cubic root of 422173721 is about 750.1769780869.

The spelling of 422173721 in words is "four hundred twenty-two million, one hundred seventy-three thousand, seven hundred twenty-one".