1213311191 has 2 divisors, whose sum is σ = 1213311192. Its totient is φ = 1213311190.

The previous prime is 1213311161. The next prime is 1213311217. The reversal of 1213311191 is 1911133121.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (1911133121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1213311191 - 2¹⁰ = 1213310167 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1213311161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606655595 + 606655596.

It is an arithmetic number, because the mean of its divisors is an integer number (606655596).

Almost surely, 2^1213311191 is an apocalyptic number.

1213311191 is a deficient number, since it is larger than the sum of its proper divisors (1).

1213311191 is an equidigital number, since it uses as much as digits as its factorization.

1213311191 is an evil number, because the sum of its binary digits is even.

The product of its digits is 162, while the sum is 23.

The square root of 1213311191 is about 34832.6167693442. The cubic root of 1213311191 is about 1066.5733659387.

The spelling of 1213311191 in words is "one billion, two hundred thirteen million, three hundred eleven thousand, one hundred ninety-one".