1328766221 has 8 divisors (see below), whose sum is σ = 1351749120. Its totient is φ = 1305912672.

The previous prime is 1328766217. The next prime is 1328766247. The reversal of 1328766221 is 1226678231.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1328766221 - 2² = 1328766217 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1328766211) 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, 11501 + ... + 52818.

It is an arithmetic number, because the mean of its divisors is an integer number (168968640).

Almost surely, 2^1328766221 is an apocalyptic number.

It is an amenable number.

1328766221 is a deficient number, since it is larger than the sum of its proper divisors (22982899).

1328766221 is an equidigital number, since it uses as much as digits as its factorization.

1328766221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64675.

The product of its digits is 48384, while the sum is 38.

The square root of 1328766221 is about 36452.2457607210. The cubic root of 1328766221 is about 1099.3842893126.

The spelling of 1328766221 in words is "one billion, three hundred twenty-eight million, seven hundred sixty-six thousand, two hundred twenty-one".