1491327191 has 2 divisors, whose sum is σ = 1491327192. Its totient is φ = 1491327190.

The previous prime is 1491327169. The next prime is 1491327203. The reversal of 1491327191 is 1917231941.

It is a strong prime.

It is an emirp because it is prime and its reverse (1917231941) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1491327191 - 2⁶ = 1491327127 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1491327391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 745663595 + 745663596.

It is an arithmetic number, because the mean of its divisors is an integer number (745663596).

Almost surely, 2^1491327191 is an apocalyptic number.

1491327191 is a deficient number, since it is larger than the sum of its proper divisors (1).

1491327191 is an equidigital number, since it uses as much as digits as its factorization.

1491327191 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13608, while the sum is 38.

The square root of 1491327191 is about 38617.7056672195. The cubic root of 1491327191 is about 1142.5037795284.

The spelling of 1491327191 in words is "one billion, four hundred ninety-one million, three hundred twenty-seven thousand, one hundred ninety-one".