6638805120 has 128 divisors (see below), whose sum is σ = 21230720640. Its totient is φ = 1764532224.

The previous prime is 6638805113. The next prime is 6638805149. The reversal of 6638805120 is 215088366.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (128).

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 15 ways as a sum of consecutive naturals, for example, 595437 + ... + 606483.

It is an arithmetic number, because the mean of its divisors is an integer number (165865005).

Almost surely, 2^6638805120 is an apocalyptic number.

6638805120 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 6638805120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10615360320).

6638805120 is an abundant number, since it is smaller than the sum of its proper divisors (14591915520).

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

6638805120 is a wasteful number, since it uses less digits than its factorization.

6638805120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11382 (or 11370 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 39.

The square root of 6638805120 is about 81478.8630259407. The cubic root of 6638805120 is about 1879.4465248644.

The spelling of 6638805120 in words is "six billion, six hundred thirty-eight million, eight hundred five thousand, one hundred twenty".