20587 has 8 divisors (see below), whose sum is σ = 25056. Its totient is φ = 16512.

The previous prime is 20563. The next prime is 20593. The reversal of 20587 is 78502.

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 20587 - 2¹¹ = 18539 is a prime.

It is a Duffinian number.

20587 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (20507) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33 + ... + 205.

It is an arithmetic number, because the mean of its divisors is an integer number (3132).

2²⁰⁵⁸⁷ is an apocalyptic number.

20587 is a deficient number, since it is larger than the sum of its proper divisors (4469).

20587 is a wasteful number, since it uses less digits than its factorization.

20587 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 197.

The product of its (nonzero) digits is 560, while the sum is 22.

The square root of 20587 is about 143.4817061510. The cubic root of 20587 is about 27.4071801738.

It can be divided in two parts, 205 and 87, that added together give a palindrome (292).

The spelling of 20587 in words is "twenty thousand, five hundred eighty-seven".