6545 has 16 divisors (see below), whose sum is σ = 10368. Its totient is φ = 3840.

The previous prime is 6529. The next prime is 6547. The reversal of 6545 is 5456.

6545 = T₁ + T₂ + ... + T₃₃.

6545 = 11² + 12² + ... + 27².

6545 is nontrivially palindromic in base 16.

6545 is an esthetic number in base 4 and base 10, because in such bases its adjacent digits differ by 1.

6545 is a nontrivial binomial coefficient, being equal to C(35, 3).

It is not a de Polignac number, because 6545 - 2⁴ = 6529 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

Its product of digits (600) is a multiple of the sum of its prime divisors (40).

It is a plaindrome in base 14.

It is a nialpdrome in base 9.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6547) by changing a digit.

It is the 33-rd tetrahedral number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 377 + ... + 393.

It is an arithmetic number, because the mean of its divisors is an integer number (648).

2⁶⁵⁴⁵ is an apocalyptic number.

It is an amenable number.

6545 is a deficient number, since it is larger than the sum of its proper divisors (3823).

6545 is a wasteful number, since it uses less digits than its factorization.

6545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40.

The product of its digits is 600, while the sum is 20.

The square root of 6545 is about 80.9011742807. The cubic root of 6545 is about 18.7055242146.

Subtracting from 6545 its reverse (5456), we obtain a square (1089 = 33²).

The spelling of 6545 in words is "six thousand, five hundred forty-five".