91398689 has 2 divisors, whose sum is σ = 91398690. Its totient is φ = 91398688.

The previous prime is 91398673. The next prime is 91398707. The reversal of 91398689 is 98689319.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 85248289 + 6150400 = 9233^2 + 2480^2 .

It is a cyclic number.

It is not a de Polignac number, because 91398689 - 2⁴ = 91398673 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 91398689.

It is not a weakly prime, because it can be changed into another prime (91398589) 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, 45699344 + 45699345.

It is an arithmetic number, because the mean of its divisors is an integer number (45699345).

Almost surely, 2^91398689 is an apocalyptic number.

It is an amenable number.

91398689 is a deficient number, since it is larger than the sum of its proper divisors (1).

91398689 is an equidigital number, since it uses as much as digits as its factorization.

91398689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 839808, while the sum is 53.

The square root of 91398689 is about 9560.2661573829. The cubic root of 91398689 is about 450.4500665892.

The spelling of 91398689 in words is "ninety-one million, three hundred ninety-eight thousand, six hundred eighty-nine".