20545 has 8 divisors (see below), whose sum is σ = 28224. Its totient is φ = 14064.

The previous prime is 20543. The next prime is 20549. The reversal of 20545 is 54502.

It is a happy number.

20545 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

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 20545 - 2¹ = 20543 is a prime.

20545 is strictly pandigital in base 6.

It is a plaindrome in base 11.

It is a nialpdrome in base 12.

It is not an unprimeable number, because it can be changed into a prime (20543) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 259 + ... + 328.

It is an arithmetic number, because the mean of its divisors is an integer number (3528).

2²⁰⁵⁴⁵ is an apocalyptic number.

It is an amenable number.

20545 is a deficient number, since it is larger than the sum of its proper divisors (7679).

20545 is an equidigital number, since it uses as much as digits as its factorization.

20545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 599.

The product of its (nonzero) digits is 200, while the sum is 16.

The square root of 20545 is about 143.3352713047. The cubic root of 20545 is about 27.3885294840.

It can be divided in two parts, 20 and 545, that added together give a palindrome (565).

The spelling of 20545 in words is "twenty thousand, five hundred forty-five".