6443920 has 80 divisors (see below), whose sum is σ = 17641728. Its totient is φ = 2142720.

The previous prime is 6443917. The next prime is 6443947. The reversal of 6443920 is 293446.

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 (28).

It is a d-powerful number, because it can be written as 6² + 4⁵ + 4⁸ + 3¹³ + 9⁷ + 2⁵ + 0 .

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20565 + ... + 20875.

Almost surely, 2^6443920 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6443920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8820864).

6443920 is an abundant number, since it is smaller than the sum of its proper divisors (11197808).

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

6443920 is a wasteful number, since it uses less digits than its factorization.

6443920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 368 (or 362 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 28.

The square root of 6443920 is about 2538.4877387925. The cubic root of 6443920 is about 186.0872908963.

The spelling of 6443920 in words is "six million, four hundred forty-three thousand, nine hundred twenty".