989978900 has 18 divisors (see below), whose sum is σ = 2148254430. Its totient is φ = 395991520.

The previous prime is 989978881. The next prime is 989978929. The reversal of 989978900 is 9879989.

It can be written as a sum of positive squares in 3 ways, for example, as 271524484 + 718454416 = 16478^2 + 26804^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 989978900.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4949795 + ... + 4949994.

Almost surely, 2^989978900 is an apocalyptic number.

It is an amenable number.

989978900 is an abundant number, since it is smaller than the sum of its proper divisors (1158275530).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

989978900 is a wasteful number, since it uses less digits than its factorization.

989978900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9899803 (or 9899796 counting only the distinct ones).

The product of its (nonzero) digits is 2939328, while the sum is 59.

The square root of 989978900 is about 31463.9301423074. The cubic root of 989978900 is about 996.6484127458.

The spelling of 989978900 in words is "nine hundred eighty-nine million, nine hundred seventy-eight thousand, nine hundred".