1217240191 has 2 divisors, whose sum is σ = 1217240192. Its totient is φ = 1217240190.

The previous prime is 1217240159. The next prime is 1217240197. The reversal of 1217240191 is 1910427121.

It is a strong prime.

It is an emirp because it is prime and its reverse (1910427121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1217240191 - 2⁵ = 1217240159 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1217240197) 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 as a sum of consecutive naturals, namely, 608620095 + 608620096.

It is an arithmetic number, because the mean of its divisors is an integer number (608620096).

Almost surely, 2^1217240191 is an apocalyptic number.

1217240191 is a deficient number, since it is larger than the sum of its proper divisors (1).

1217240191 is an equidigital number, since it uses as much as digits as its factorization.

1217240191 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1008, while the sum is 28.

The square root of 1217240191 is about 34888.9694746062. The cubic root of 1217240191 is about 1067.7234010778.

The spelling of 1217240191 in words is "one billion, two hundred seventeen million, two hundred forty thousand, one hundred ninety-one".