6721228800 has 1248 divisors, whose sum is σ = 30714284160. Its totient is φ = 1415577600.

The previous prime is 6721228757. The next prime is 6721228831. The reversal of 6721228800 is 88221276.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (1248).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 395366392 + ... + 395366408.

Almost surely, 2^6721228800 is an apocalyptic number.

6721228800 is a gapful number since it is divisible by the number (60) 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 6721228800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15357142080).

6721228800 is an abundant number, since it is smaller than the sum of its proper divisors (23993055360).

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

6721228800 is a wasteful number, since it uses less digits than its factorization.

6721228800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84 (or 51 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 6721228800 is about 81983.1006976438. The cubic root of 6721228800 is about 1887.1926069888.

The spelling of 6721228800 in words is "six billion, seven hundred twenty-one million, two hundred twenty-eight thousand, eight hundred".