985878991 has 2 divisors, whose sum is σ = 985878992. Its totient is φ = 985878990.

The previous prime is 985878961. The next prime is 985879039. The reversal of 985878991 is 199878589.

It is a weak prime.

It is an emirp because it is prime and its reverse (199878589) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 985878991 - 2¹¹ = 985876943 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (985878941) 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, 492939495 + 492939496.

It is an arithmetic number, because the mean of its divisors is an integer number (492939496).

Almost surely, 2^985878991 is an apocalyptic number.

985878991 is a deficient number, since it is larger than the sum of its proper divisors (1).

985878991 is an equidigital number, since it uses as much as digits as its factorization.

985878991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13063680, while the sum is 64.

The square root of 985878991 is about 31398.7100212732. The cubic root of 985878991 is about 995.2706656564.

The spelling of 985878991 in words is "nine hundred eighty-five million, eight hundred seventy-eight thousand, nine hundred ninety-one".