1328446561 has 8 divisors (see below), whose sum is σ = 1434243944. Its totient is φ = 1223164800.

The previous prime is 1328446523. The next prime is 1328446571. The reversal of 1328446561 is 1656448231.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 326344225 + 1002102336 = 18065^2 + 31656^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1328446561 - 2¹³ = 1328438369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1328446501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 123540 + ... + 133861.

It is an arithmetic number, because the mean of its divisors is an integer number (179280493).

Almost surely, 2^1328446561 is an apocalyptic number.

It is an amenable number.

1328446561 is a deficient number, since it is larger than the sum of its proper divisors (105797383).

1328446561 is a wasteful number, since it uses less digits than its factorization.

1328446561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 257811.

The product of its digits is 138240, while the sum is 40.

The square root of 1328446561 is about 36447.8608562972. The cubic root of 1328446561 is about 1099.2961229717.

The spelling of 1328446561 in words is "one billion, three hundred twenty-eight million, four hundred forty-six thousand, five hundred sixty-one".