1891133291 has 2 divisors, whose sum is σ = 1891133292. Its totient is φ = 1891133290.

The previous prime is 1891133267. The next prime is 1891133303. The reversal of 1891133291 is 1923311981.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1891133291 - 2¹⁰ = 1891132267 is a prime.

It is not a weakly prime, because it can be changed into another prime (1891133221) 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, 945566645 + 945566646.

It is an arithmetic number, because the mean of its divisors is an integer number (945566646).

Almost surely, 2^1891133291 is an apocalyptic number.

1891133291 is a deficient number, since it is larger than the sum of its proper divisors (1).

1891133291 is an equidigital number, since it uses as much as digits as its factorization.

1891133291 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11664, while the sum is 38.

The square root of 1891133291 is about 43487.1623700604. The cubic root of 1891133291 is about 1236.6326630807.

The spelling of 1891133291 in words is "one billion, eight hundred ninety-one million, one hundred thirty-three thousand, two hundred ninety-one".