128287717 has 2 divisors, whose sum is σ = 128287718. Its totient is φ = 128287716.

The previous prime is 128287667. The next prime is 128287739. The reversal of 128287717 is 717782821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 119443041 + 8844676 = 10929^2 + 2974^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128287717 is a prime.

It is a super-3 number, since 3×128287717³ (a number of 25 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128287787) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64143858 + 64143859.

It is an arithmetic number, because the mean of its divisors is an integer number (64143859).

Almost surely, 2^128287717 is an apocalyptic number.

It is an amenable number.

128287717 is a deficient number, since it is larger than the sum of its proper divisors (1).

128287717 is an equidigital number, since it uses as much as digits as its factorization.

128287717 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 87808, while the sum is 43.

The square root of 128287717 is about 11326.4167767216. The cubic root of 128287717 is about 504.3457422861.

The spelling of 128287717 in words is "one hundred twenty-eight million, two hundred eighty-seven thousand, seven hundred seventeen".