8389840 has 80 divisors (see below), whose sum is σ = 21427200. Its totient is φ = 3041280.

The previous prime is 8389837. The next prime is 8389877. The reversal of 8389840 is 489838.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 8389793 and 8389802.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42061 + ... + 42259.

It is an arithmetic number, because the mean of its divisors is an integer number (267840).

Almost surely, 2^8389840 is an apocalyptic number.

8389840 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 8389840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10713600).

8389840 is an abundant number, since it is smaller than the sum of its proper divisors (13037360).

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

8389840 is a wasteful number, since it uses less digits than its factorization.

8389840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 260 (or 254 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 40.

The square root of 8389840 is about 2896.5220523932. The cubic root of 8389840 is about 203.1972812582.

It can be divided in two parts, 83898 and 40, that added together give a palindrome (83938).

The spelling of 8389840 in words is "eight million, three hundred eighty-nine thousand, eight hundred forty".