991087067 has 2 divisors, whose sum is σ = 991087068. Its totient is φ = 991087066.

The previous prime is 991087061. The next prime is 991087087. The reversal of 991087067 is 760780199.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 991087067 - 2¹² = 991082971 is a prime.

It is not a weakly prime, because it can be changed into another prime (991087061) 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, 495543533 + 495543534.

It is an arithmetic number, because the mean of its divisors is an integer number (495543534).

Almost surely, 2^991087067 is an apocalyptic number.

991087067 is a deficient number, since it is larger than the sum of its proper divisors (1).

991087067 is an equidigital number, since it uses as much as digits as its factorization.

991087067 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 190512, while the sum is 47.

The square root of 991087067 is about 31481.5353342241. The cubic root of 991087067 is about 997.0201516570.

The spelling of 991087067 in words is "nine hundred ninety-one million, eighty-seven thousand, sixty-seven".