1328103991 has 2 divisors, whose sum is σ = 1328103992. Its totient is φ = 1328103990.

The previous prime is 1328103979. The next prime is 1328104007. The reversal of 1328103991 is 1993018231.

It is a weak prime.

It is an emirp because it is prime and its reverse (1993018231) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1328103991 - 2¹³ = 1328095799 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1328103991.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1328103941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 664051995 + 664051996.

It is an arithmetic number, because the mean of its divisors is an integer number (664051996).

Almost surely, 2^1328103991 is an apocalyptic number.

1328103991 is a deficient number, since it is larger than the sum of its proper divisors (1).

1328103991 is an equidigital number, since it uses as much as digits as its factorization.

1328103991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11664, while the sum is 37.

The square root of 1328103991 is about 36443.1611005412. The cubic root of 1328103991 is about 1099.2016220564.

The spelling of 1328103991 in words is "one billion, three hundred twenty-eight million, one hundred three thousand, nine hundred ninety-one".