989555993 has 2 divisors, whose sum is σ = 989555994. Its totient is φ = 989555992.

The previous prime is 989555989. The next prime is 989556011. The reversal of 989555993 is 399555989.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 580424464 + 409131529 = 24092^2 + 20227^2 .

It is a cyclic number.

It is not a de Polignac number, because 989555993 - 2² = 989555989 is a prime.

It is not a weakly prime, because it can be changed into another prime (989551993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 494777996 + 494777997.

It is an arithmetic number, because the mean of its divisors is an integer number (494777997).

Almost surely, 2^989555993 is an apocalyptic number.

It is an amenable number.

989555993 is a deficient number, since it is larger than the sum of its proper divisors (1).

989555993 is an equidigital number, since it uses as much as digits as its factorization.

989555993 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 19683000, while the sum is 62.

The square root of 989555993 is about 31457.2089194194. The cubic root of 989555993 is about 996.5064738207.

The spelling of 989555993 in words is "nine hundred eighty-nine million, five hundred fifty-five thousand, nine hundred ninety-three".