6444220720 has 80 divisors (see below), whose sum is σ = 17413528320. Its totient is φ = 2171987712.

The previous prime is 6444220711. The next prime is 6444220721. The reversal of 6444220720 is 270224446.

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

It is not an unprimeable number, because it can be changed into a prime (6444220721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 64482 + ... + 130561.

It is an arithmetic number, because the mean of its divisors is an integer number (217669104).

Almost surely, 2^6444220720 is an apocalyptic number.

It is an amenable number.

6444220720 is an abundant number, since it is smaller than the sum of its proper divisors (10969307600).

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

6444220720 is a wasteful number, since it uses less digits than its factorization.

6444220720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195122 (or 195116 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 31.

The square root of 6444220720 is about 80275.9037320664. The cubic root of 6444220720 is about 1860.9018557837.

The spelling of 6444220720 in words is "six billion, four hundred forty-four million, two hundred twenty thousand, seven hundred twenty".