91587 has 4 divisors (see below), whose sum is σ = 122120. Its totient is φ = 61056.

The previous prime is 91583. The next prime is 91591. The reversal of 91587 is 78519.

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

It is an interprime number because it is at equal distance from previous prime (91583) and next prime (91591).

It is not a de Polignac number, because 91587 - 2² = 91583 is a prime.

It is a D-number.

It is a Duffinian number.

91587 is a lucky number.

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 91587.

It is not an unprimeable number, because it can be changed into a prime (91583) 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, 15262 + ... + 15267.

It is an arithmetic number, because the mean of its divisors is an integer number (30530).

2⁹¹⁵⁸⁷ is an apocalyptic number.

91587 is a deficient number, since it is larger than the sum of its proper divisors (30533).

91587 is a wasteful number, since it uses less digits than its factorization.

91587 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30532.

The product of its digits is 2520, while the sum is 30.

The square root of 91587 is about 302.6334416419. The cubic root of 91587 is about 45.0759212211.

It can be divided in two parts, 9 and 1587, that added together give a triangular number (1596 = T₅₆).

The spelling of 91587 in words is "ninety-one thousand, five hundred eighty-seven".