1320328728 has 64 divisors (see below), whose sum is σ = 3673404000. Its totient is φ = 439410816.

The previous prime is 1320328687. The next prime is 1320328729. The reversal of 1320328728 is 8278230231.

It is a happy number.

1320328728 is a `hidden beast` number, since 1 + 320 + 328 + 7 + 2 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1320328692 and 1320328701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1320328729) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 141718 + ... + 150746.

Almost surely, 2^1320328728 is an apocalyptic number.

1320328728 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

1320328728 is an abundant number, since it is smaller than the sum of its proper divisors (2353075272).

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

1320328728 is a wasteful number, since it uses less digits than its factorization.

1320328728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9721 (or 9711 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 1320328728 is about 36336.3279377540. The cubic root of 1320328728 is about 1097.0523640137.

Adding to 1320328728 its reverse (8278230231), we get a palindrome (9598558959).

The spelling of 1320328728 in words is "one billion, three hundred twenty million, three hundred twenty-eight thousand, seven hundred twenty-eight".