999998566681069 has 2 divisors, whose sum is σ = 999998566681070. Its totient is φ = 999998566681068.

The previous prime is 999998566681021. The next prime is 999998566681223. The reversal of 999998566681069 is 960186665899999.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 956911551716169 + 43087014964900 = 30933987^2 + 6564070^2 .

It is a cyclic number.

It is not a de Polignac number, because 999998566681069 - 2³¹ = 999996419197421 is a prime.

It is a super-2 number, since 2×999998566681069² (a number of 31 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999998566681369) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499999283340534 + 499999283340535.

It is an arithmetic number, because the mean of its divisors is an integer number (499999283340535).

Almost surely, 2^{999998566681069} is an apocalyptic number.

It is an amenable number.

999998566681069 is a deficient number, since it is larger than the sum of its proper divisors (1).

999998566681069 is an equidigital number, since it uses as much as digits as its factorization.

999998566681069 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 220399211520, while the sum is 100.

The spelling of 999998566681069 in words is "nine hundred ninety-nine trillion, nine hundred ninety-eight billion, five hundred sixty-six million, six hundred eighty-one thousand, sixty-nine".