91243091 has 2 divisors, whose sum is σ = 91243092. Its totient is φ = 91243090.

The previous prime is 91243049. The next prime is 91243099. The reversal of 91243091 is 19034219.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 91243091 - 2¹⁸ = 90980947 is a prime.

It is not a weakly prime, because it can be changed into another prime (91243099) 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, 45621545 + 45621546.

It is an arithmetic number, because the mean of its divisors is an integer number (45621546).

Almost surely, 2^91243091 is an apocalyptic number.

91243091 is a deficient number, since it is larger than the sum of its proper divisors (1).

91243091 is an equidigital number, since it uses as much as digits as its factorization.

91243091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 91243091 is about 9552.1249468377. The cubic root of 91243091 is about 450.1943045669.

The spelling of 91243091 in words is "ninety-one million, two hundred forty-three thousand, ninety-one".