1328581660 has 48 divisors (see below), whose sum is σ = 3327238656. Its totient is φ = 435707712.

The previous prime is 1328581643. The next prime is 1328581697. The reversal of 1328581660 is 661858231.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 203082 + ... + 209521.

It is an arithmetic number, because the mean of its divisors is an integer number (69317472).

Almost surely, 2^1328581660 is an apocalyptic number.

1328581660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1328581660 is an abundant number, since it is smaller than the sum of its proper divisors (1998656996).

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

1328581660 is a wasteful number, since it uses less digits than its factorization.

1328581660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 412642 (or 412640 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 40.

The square root of 1328581660 is about 36449.7141278227. The cubic root of 1328581660 is about 1099.3333867395. Note that the first 4 decimals are identical.

The spelling of 1328581660 in words is "one billion, three hundred twenty-eight million, five hundred eighty-one thousand, six hundred sixty".