999998881117 has 2 divisors, whose sum is σ = 999998881118. Its totient is φ = 999998881116.

The previous prime is 999998881111. The next prime is 999998881169. The reversal of 999998881117 is 711188899999.

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., 980325732996 + 19673148121 = 990114^2 + 140261^2 .

It is a cyclic number.

It is not a de Polignac number, because 999998881117 - 2³⁵ = 965639142749 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999998881111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499999440558 + 499999440559.

It is an arithmetic number, because the mean of its divisors is an integer number (499999440559).

Almost surely, 2^999998881117 is an apocalyptic number.

It is an amenable number.

999998881117 is a deficient number, since it is larger than the sum of its proper divisors (1).

999998881117 is an equidigital number, since it uses as much as digits as its factorization.

999998881117 is an evil number, because the sum of its binary digits is even.

The product of its digits is 211631616, while the sum is 79.

The spelling of 999998881117 in words is "nine hundred ninety-nine billion, nine hundred ninety-eight million, eight hundred eighty-one thousand, one hundred seventeen".