6639122880 has 1120 divisors, whose sum is σ = 28811280960. Its totient is φ = 1433272320.

The previous prime is 6639122869. The next prime is 6639122881. The reversal of 6639122880 is 882219366.

6639122880 is a `hidden beast` number, since 6 + 639 + 1 + 2 + 2 + 8 + 8 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6639122881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 108838050 + ... + 108838110.

It is an arithmetic number, because the mean of its divisors is an integer number (25724358).

Almost surely, 2^6639122880 is an apocalyptic number.

6639122880 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 6639122880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14405640480).

6639122880 is an abundant number, since it is smaller than the sum of its proper divisors (22172158080).

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

6639122880 is a wasteful number, since it uses less digits than its factorization.

6639122880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139 (or 120 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 45.

The square root of 6639122880 is about 81480.8129561801. The cubic root of 6639122880 is about 1879.4765103506.

The spelling of 6639122880 in words is "six billion, six hundred thirty-nine million, one hundred twenty-two thousand, eight hundred eighty".