991134491 has 2 divisors, whose sum is σ = 991134492. Its totient is φ = 991134490.

The previous prime is 991134439. The next prime is 991134499. The reversal of 991134491 is 194431199.

991134491 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 991134491 - 2¹⁸ = 990872347 is a prime.

It is not a weakly prime, because it can be changed into another prime (991134499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495567245 + 495567246.

It is an arithmetic number, because the mean of its divisors is an integer number (495567246).

Almost surely, 2^991134491 is an apocalyptic number.

991134491 is a deficient number, since it is larger than the sum of its proper divisors (1).

991134491 is an equidigital number, since it uses as much as digits as its factorization.

991134491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34992, while the sum is 41.

The square root of 991134491 is about 31482.2885286315. The cubic root of 991134491 is about 997.0360540371.

The spelling of 991134491 in words is "nine hundred ninety-one million, one hundred thirty-four thousand, four hundred ninety-one".