421317217 has 2 divisors, whose sum is σ = 421317218. Its totient is φ = 421317216.

The previous prime is 421317209. The next prime is 421317233. The reversal of 421317217 is 712713124.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 373416976 + 47900241 = 19324^2 + 6921^2 .

It is a cyclic number.

It is not a de Polignac number, because 421317217 - 2³ = 421317209 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (421317287) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210658608 + 210658609.

It is an arithmetic number, because the mean of its divisors is an integer number (210658609).

Almost surely, 2^421317217 is an apocalyptic number.

It is an amenable number.

421317217 is a deficient number, since it is larger than the sum of its proper divisors (1).

421317217 is an equidigital number, since it uses as much as digits as its factorization.

421317217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2352, while the sum is 28.

The square root of 421317217 is about 20526.0131784036. The cubic root of 421317217 is about 749.6693161449.

The spelling of 421317217 in words is "four hundred twenty-one million, three hundred seventeen thousand, two hundred seventeen".