989813687 has 4 divisors (see below), whose sum is σ = 990419976. Its totient is φ = 989207400.

The previous prime is 989813681. The next prime is 989813707. The reversal of 989813687 is 786318989.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 786318989 = 73 ⋅10771493.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-989813687 is a prime.

It is a super-2 number, since 2×989813687² = 1959462269945067938, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (989813681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 300689 + ... + 303962.

It is an arithmetic number, because the mean of its divisors is an integer number (247604994).

Almost surely, 2^989813687 is an apocalyptic number.

989813687 is a deficient number, since it is larger than the sum of its proper divisors (606289).

989813687 is a wasteful number, since it uses less digits than its factorization.

989813687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 606288.

The product of its digits is 5225472, while the sum is 59.

The square root of 989813687 is about 31461.3045978707. The cubic root of 989813687 is about 996.5929676467.

The spelling of 989813687 in words is "nine hundred eighty-nine million, eight hundred thirteen thousand, six hundred eighty-seven".