91378193 has 2 divisors, whose sum is σ = 91378194. Its totient is φ = 91378192.

The previous prime is 91378187. The next prime is 91378211. The reversal of 91378193 is 39187319.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 86638864 + 4739329 = 9308^2 + 2177^2 .

It is a cyclic number.

It is not a de Polignac number, because 91378193 - 2⁶ = 91378129 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 91378193.

It is not a weakly prime, because it can be changed into another prime (91378093) 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, 45689096 + 45689097.

It is an arithmetic number, because the mean of its divisors is an integer number (45689097).

Almost surely, 2^91378193 is an apocalyptic number.

It is an amenable number.

91378193 is a deficient number, since it is larger than the sum of its proper divisors (1).

91378193 is an equidigital number, since it uses as much as digits as its factorization.

91378193 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40824, while the sum is 41.

The square root of 91378193 is about 9559.1941605974. The cubic root of 91378193 is about 450.4163931858.

The spelling of 91378193 in words is "ninety-one million, three hundred seventy-eight thousand, one hundred ninety-three".