1191912011 has 2 divisors, whose sum is σ = 1191912012. Its totient is φ = 1191912010.

The previous prime is 1191911999. The next prime is 1191912017. The reversal of 1191912011 is 1102191911.

It is a strong prime.

It is an emirp because it is prime and its reverse (1102191911) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1191912011 - 2³⁰ = 118170187 is a prime.

It is not a weakly prime, because it can be changed into another prime (1191912017) 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, 595956005 + 595956006.

It is an arithmetic number, because the mean of its divisors is an integer number (595956006).

Almost surely, 2^1191912011 is an apocalyptic number.

1191912011 is a deficient number, since it is larger than the sum of its proper divisors (1).

1191912011 is an equidigital number, since it uses as much as digits as its factorization.

1191912011 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 162, while the sum is 26.

The square root of 1191912011 is about 34524.0787132691. The cubic root of 1191912011 is about 1060.2657489029.

The spelling of 1191912011 in words is "one billion, one hundred ninety-one million, nine hundred twelve thousand, eleven".