1191296321 has 2 divisors, whose sum is σ = 1191296322. Its totient is φ = 1191296320.

The previous prime is 1191296311. The next prime is 1191296329. The reversal of 1191296321 is 1236921911.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 837292096 + 354004225 = 28936^2 + 18815^2 .

It is a cyclic number.

It is not a de Polignac number, because 1191296321 - 2¹⁸ = 1191034177 is a prime.

It is not a weakly prime, because it can be changed into another prime (1191296329) 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 as a sum of consecutive naturals, namely, 595648160 + 595648161.

It is an arithmetic number, because the mean of its divisors is an integer number (595648161).

Almost surely, 2^1191296321 is an apocalyptic number.

It is an amenable number.

1191296321 is a deficient number, since it is larger than the sum of its proper divisors (1).

1191296321 is an equidigital number, since it uses as much as digits as its factorization.

1191296321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5832, while the sum is 35.

The square root of 1191296321 is about 34515.1607413322. The cubic root of 1191296321 is about 1060.0831550405.

The spelling of 1191296321 in words is "one billion, one hundred ninety-one million, two hundred ninety-six thousand, three hundred twenty-one".