6639993360 has 1280 divisors, whose sum is σ = 31917957120. Its totient is φ = 1224253440.

The previous prime is 6639993359. The next prime is 6639993377. The reversal of 6639993360 is 633999366.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a junction number, because it is equal to n+sod(n) for n = 6639993297 and 6639993306.

It is an unprimeable number.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 79999879 + ... + 79999961.

It is an arithmetic number, because the mean of its divisors is an integer number (24935904).

Almost surely, 2^6639993360 is an apocalyptic number.

6639993360 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 6639993360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15958978560).

6639993360 is an abundant number, since it is smaller than the sum of its proper divisors (25277963760).

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

6639993360 is a wasteful number, since it uses less digits than its factorization.

6639993360 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173 (or 161 counting only the distinct ones).

The product of its (nonzero) digits is 4251528, while the sum is 54.

The square root of 6639993360 is about 81486.1544067457. The cubic root of 6639993360 is about 1879.5586484706.

It can be divided in two parts, 6639 and 993360, that added together give a palindrome (999999).

The spelling of 6639993360 in words is "six billion, six hundred thirty-nine million, nine hundred ninety-three thousand, three hundred sixty".