999217717 has 2 divisors, whose sum is σ = 999217718. Its totient is φ = 999217716.

The previous prime is 999217693. The next prime is 999217777. The reversal of 999217717 is 717712999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 624950001 + 374267716 = 24999^2 + 19346^2 .

It is a cyclic number.

It is not a de Polignac number, because 999217717 - 2¹⁹ = 998693429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999217777) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499608858 + 499608859.

It is an arithmetic number, because the mean of its divisors is an integer number (499608859).

Almost surely, 2^999217717 is an apocalyptic number.

It is an amenable number.

999217717 is a deficient number, since it is larger than the sum of its proper divisors (1).

999217717 is an equidigital number, since it uses as much as digits as its factorization.

999217717 is an evil number, because the sum of its binary digits is even.

The product of its digits is 500094, while the sum is 52.

The square root of 999217717 is about 31610.4052014523. The cubic root of 999217717 is about 999.7391709741.

The spelling of 999217717 in words is "nine hundred ninety-nine million, two hundred seventeen thousand, seven hundred seventeen".