6720444864 has 252 divisors, whose sum is σ = 23133759168. Its totient is φ = 1857945600.

The previous prime is 6720444839. The next prime is 6720444869. The reversal of 6720444864 is 4684440276.

It is a tau number, because it is divible by the number of its divisors (252).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6720444869) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 871104 + ... + 878784.

Almost surely, 2^6720444864 is an apocalyptic number.

6720444864 is a gapful number since it is divisible by the number (64) 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 6720444864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11566879584).

6720444864 is an abundant number, since it is smaller than the sum of its proper divisors (16413314304).

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

6720444864 is a wasteful number, since it uses less digits than its factorization.

6720444864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7744 (or 7724 counting only the distinct ones).

The product of its (nonzero) digits is 1032192, while the sum is 45.

The square root of 6720444864 is about 81978.3194753345. The cubic root of 6720444864 is about 1887.1192327200.

It can be divided in two parts, 6720 and 444864, that added together give a square (451584 = 672²).

The spelling of 6720444864 in words is "six billion, seven hundred twenty million, four hundred forty-four thousand, eight hundred sixty-four".