8541991 has 2 divisors, whose sum is σ = 8541992. Its totient is φ = 8541990.

The previous prime is 8541983. The next prime is 8541997. The reversal of 8541991 is 1991458.

8541991 is digitally balanced in base 3, 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 8541991 - 2³ = 8541983 is a prime.

It is a super-2 number, since 2×8541991² = 145931220488162, which contains 22 as substring.

It is equal to p₅₇₃₇₈₇ and since 8541991 and 573787 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 8541991.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8541997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4270995 + 4270996.

It is an arithmetic number, because the mean of its divisors is an integer number (4270996).

Almost surely, 2^8541991 is an apocalyptic number.

8541991 is a deficient number, since it is larger than the sum of its proper divisors (1).

8541991 is an equidigital number, since it uses as much as digits as its factorization.

8541991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12960, while the sum is 37.

The square root of 8541991 is about 2922.6684724751. The cubic root of 8541991 is about 204.4182674840.

The spelling of 8541991 in words is "eight million, five hundred forty-one thousand, nine hundred ninety-one".