91439 has 4 divisors (see below), whose sum is σ = 93000. Its totient is φ = 89880.

The previous prime is 91433. The next prime is 91453. The reversal of 91439 is 93419.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 91439 - 2⁴ = 91423 is a prime.

It is a super-2 number, since 2×91439² = 16722181442, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 12.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 91439.

It is not an unprimeable number, because it can be changed into a prime (91433) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 689 + ... + 810.

It is an arithmetic number, because the mean of its divisors is an integer number (23250).

2⁹¹⁴³⁹ is an apocalyptic number.

91439 is a deficient number, since it is larger than the sum of its proper divisors (1561).

91439 is a wasteful number, since it uses less digits than its factorization.

91439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1560.

The product of its digits is 972, while the sum is 26.

The square root of 91439 is about 302.3888225447. The cubic root of 91439 is about 45.0516279879.

The spelling of 91439 in words is "ninety-one thousand, four hundred thirty-nine".