91159819 has 2 divisors, whose sum is σ = 91159820. Its totient is φ = 91159818.

The previous prime is 91159799. The next prime is 91159829. The reversal of 91159819 is 91895119.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 91159819 - 2¹⁷ = 91028747 is a prime.

It is a super-2 number, since 2×91159819² = 16620225200225522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (91159829) 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, 45579909 + 45579910.

It is an arithmetic number, because the mean of its divisors is an integer number (45579910).

Almost surely, 2^91159819 is an apocalyptic number.

91159819 is a deficient number, since it is larger than the sum of its proper divisors (1).

91159819 is an equidigital number, since it uses as much as digits as its factorization.

91159819 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 29160, while the sum is 43.

The square root of 91159819 is about 9547.7651311707. The cubic root of 91159819 is about 450.0573079278.

The spelling of 91159819 in words is "ninety-one million, one hundred fifty-nine thousand, eight hundred nineteen".