91999027 has 2 divisors, whose sum is σ = 91999028. Its totient is φ = 91999026.

The previous prime is 91999021. The next prime is 91999051. The reversal of 91999027 is 72099919.

It is a weak prime.

It is an emirp because it is prime and its reverse (72099919) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91999027 - 2⁷ = 91998899 is a prime.

It is not a weakly prime, because it can be changed into another prime (91999021) 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, 45999513 + 45999514.

It is an arithmetic number, because the mean of its divisors is an integer number (45999514).

Almost surely, 2^91999027 is an apocalyptic number.

91999027 is a deficient number, since it is larger than the sum of its proper divisors (1).

91999027 is an equidigital number, since it uses as much as digits as its factorization.

91999027 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 91854, while the sum is 46.

The square root of 91999027 is about 9591.6123253601. The cubic root of 91999027 is about 451.4341520672.

The spelling of 91999027 in words is "ninety-one million, nine hundred ninety-nine thousand, twenty-seven".