4399640 has 64 divisors (see below), whose sum is σ = 11923200. Its totient is φ = 1427328.

The previous prime is 4399639. The next prime is 4399663. The reversal of 4399640 is 469934.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 4399640.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4907 + ... + 5733.

It is an arithmetic number, because the mean of its divisors is an integer number (186300).

Almost surely, 2^4399640 is an apocalyptic number.

4399640 is a gapful number since it is divisible by the number (40) 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 4399640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5961600).

4399640 is an abundant number, since it is smaller than the sum of its proper divisors (7523560).

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

4399640 is a wasteful number, since it uses less digits than its factorization.

4399640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 864 (or 860 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 35.

The square root of 4399640 is about 2097.5318829520. The cubic root of 4399640 is about 163.8597849731.

The spelling of 4399640 in words is "four million, three hundred ninety-nine thousand, six hundred forty".