989840 has 20 divisors (see below), whose sum is σ = 2301564. Its totient is φ = 395904.

The previous prime is 989839. The next prime is 989869. The reversal of 989840 is 48989.

It can be written as a sum of positive squares in 2 ways, for example, as 430336 + 559504 = 656^2 + 748^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a junction number, because it is equal to n+sod(n) for n = 989794 and 989803.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 989840.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6107 + ... + 6266.

2⁹⁸⁹⁸⁴⁰ is an apocalyptic number.

It is an amenable number.

989840 is an abundant number, since it is smaller than the sum of its proper divisors (1311724).

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

989840 is a wasteful number, since it uses less digits than its factorization.

989840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12386 (or 12380 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 38.

The square root of 989840 is about 994.9070308325. The cubic root of 989840 is about 99.6601798641.

The spelling of 989840 in words is "nine hundred eighty-nine thousand, eight hundred forty".