1328521280 has 28 divisors (see below), whose sum is σ = 3163542060. Its totient is φ = 531408384.

The previous prime is 1328521277. The next prime is 1328521289. The reversal of 1328521280 is 821258231.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1007681536 + 320839744 = 31744^2 + 17912^2 .

It is a Harshad number since it is a multiple of its sum of digits (32).

It is not an unprimeable number, because it can be changed into a prime (1328521289) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 2075495 + ... + 2076134.

It is an arithmetic number, because the mean of its divisors is an integer number (112983645).

Almost surely, 2^1328521280 is an apocalyptic number.

1328521280 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1328521280 is an abundant number, since it is smaller than the sum of its proper divisors (1835020780).

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

1328521280 is an equidigital number, since it uses as much as digits as its factorization.

1328521280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4151646 (or 4151636 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 32.

The square root of 1328521280 is about 36448.8858540285. The cubic root of 1328521280 is about 1099.3167326998.

The spelling of 1328521280 in words is "one billion, three hundred twenty-eight million, five hundred twenty-one thousand, two hundred eighty".