91389 has 8 divisors (see below), whose sum is σ = 124992. Its totient is φ = 59360.

The previous prime is 91387. The next prime is 91393. The reversal of 91389 is 98319.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 91389 - 2¹ = 91387 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91381) 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 in 7 ways as a sum of consecutive naturals, for example, 249 + ... + 494.

It is an arithmetic number, because the mean of its divisors is an integer number (15624).

2⁹¹³⁸⁹ is an apocalyptic number.

It is an amenable number.

91389 is a deficient number, since it is larger than the sum of its proper divisors (33603).

91389 is a wasteful number, since it uses less digits than its factorization.

91389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 787.

The product of its digits is 1944, while the sum is 30.

The square root of 91389 is about 302.3061362262. The cubic root of 91389 is about 45.0434148910.

Adding to 91389 its sum of digits (30), we get a palindrome (91419).

The spelling of 91389 in words is "ninety-one thousand, three hundred eighty-nine".