6556999680 is a `hidden beast` number, since 6 + 5 + 569 + 9 + 9 + 68 + 0 = 666.
It is a tau number, because it is divible by the number of its divisors (1008).
It is a congruent number.
It is an unprimeable number.
Almost surely, 26556999680 is an apocalyptic number.
6556999680 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 6556999680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14903942760).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
6556999680 is a wasteful number, since it uses less digits than its factorization.
6556999680 is an evil number, because the sum of its binary digits is even.
The square root of 6556999680 is about 80975.3029015638. The cubic root of 6556999680 is about 1871.6948878144.
The spelling of 6556999680 in words is "six billion, five hundred fifty-six million, nine hundred ninety-nine thousand, six hundred eighty".