989979990 has 64 divisors (see below), whose sum is σ = 2514240000. Its totient is φ = 248776704.

The previous prime is 989979983. The next prime is 989980003. The reversal of 989979990 is 99979989.

989979990 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 105511 + ... + 114509.

It is an arithmetic number, because the mean of its divisors is an integer number (39285000).

Almost surely, 2^989979990 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 989979990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1257120000).

989979990 is an abundant number, since it is smaller than the sum of its proper divisors (1524260010).

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

989979990 is a wasteful number, since it uses less digits than its factorization.

989979990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9221.

The product of its (nonzero) digits is 29760696, while the sum is 69.

The square root of 989979990 is about 31463.9474637243. The cubic root of 989979990 is about 996.6487785268.

The spelling of 989979990 in words is "nine hundred eighty-nine million, nine hundred seventy-nine thousand, nine hundred ninety".