987808789 has 6 divisors (see below), whose sum is σ = 1085773430. Its totient is φ = 898007880.

The previous prime is 987808781. The next prime is 987808799.

987808789 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in only one way, i.e., 982822500 + 4986289 = 31350^2 + 2233^2 .

It is not a de Polignac number, because 987808789 - 2³ = 987808781 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 987808789.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (987808781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4081734 + ... + 4081975.

Almost surely, 2^987808789 is an apocalyptic number.

It is an amenable number.

987808789 is a deficient number, since it is larger than the sum of its proper divisors (97964641).

987808789 is a wasteful number, since it uses less digits than its factorization.

987808789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8163731 (or 8163720 counting only the distinct ones).

The product of its (nonzero) digits is 16257024, while the sum is 64.

The square root of 987808789 is about 31429.4255276803. The cubic root of 987808789 is about 995.9196362770.

The spelling of 987808789 in words is "nine hundred eighty-seven million, eight hundred eight thousand, seven hundred eighty-nine".