1191492779 has 2 divisors, whose sum is σ = 1191492780. Its totient is φ = 1191492778.

The previous prime is 1191492769. The next prime is 1191492803. The reversal of 1191492779 is 9772941911.

It is a weak prime.

It is an emirp because it is prime and its reverse (9772941911) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1191492779 - 2²⁸ = 923057323 is a prime.

It is not a weakly prime, because it can be changed into another prime (1191492749) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 595746389 + 595746390.

It is an arithmetic number, because the mean of its divisors is an integer number (595746390).

Almost surely, 2^1191492779 is an apocalyptic number.

1191492779 is a deficient number, since it is larger than the sum of its proper divisors (1).

1191492779 is an equidigital number, since it uses as much as digits as its factorization.

1191492779 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 285768, while the sum is 50.

The square root of 1191492779 is about 34518.0065907636. The cubic root of 1191492779 is about 1060.1414250012.

The spelling of 1191492779 in words is "one billion, one hundred ninety-one million, four hundred ninety-two thousand, seven hundred seventy-nine".