1328388660 has 144 divisors (see below), whose sum is σ = 4194904896. Its totient is φ = 352864512.

The previous prime is 1328388647. The next prime is 1328388671. The reversal of 1328388660 is 668838231.

1328388660 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2152672 + ... + 2153288.

It is an arithmetic number, because the mean of its divisors is an integer number (29131284).

Almost surely, 2^1328388660 is an apocalyptic number.

1328388660 is a gapful number since it is divisible by the number (10) 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 1328388660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2097452448).

1328388660 is an abundant number, since it is smaller than the sum of its proper divisors (2866516236).

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

1328388660 is a wasteful number, since it uses less digits than its factorization.

1328388660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1084 (or 1070 counting only the distinct ones).

The product of its (nonzero) digits is 331776, while the sum is 45.

The square root of 1328388660 is about 36447.0665486264. The cubic root of 1328388660 is about 1099.2801516180.

The spelling of 1328388660 in words is "one billion, three hundred twenty-eight million, three hundred eighty-eight thousand, six hundred sixty".