999989863 has 2 divisors, whose sum is σ = 999989864. Its totient is φ = 999989862.

The previous prime is 999989857. The next prime is 999989899. The reversal of 999989863 is 368989999.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-999989863 is a prime.

It is a super-2 number, since 2×999989863² = 1999959452205517538, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 999989792 and 999989801.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999981863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499994931 + 499994932.

It is an arithmetic number, because the mean of its divisors is an integer number (499994932).

Almost surely, 2^999989863 is an apocalyptic number.

999989863 is a deficient number, since it is larger than the sum of its proper divisors (1).

999989863 is an equidigital number, since it uses as much as digits as its factorization.

999989863 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 68024448, while the sum is 70.

The square root of 999989863 is about 31622.6163212344. The cubic root of 999989863 is about 999.9966209886.

The spelling of 999989863 in words is "nine hundred ninety-nine million, nine hundred eighty-nine thousand, eight hundred sixty-three".