64521 has 12 divisors (see below), whose sum is σ = 95472. Its totient is φ = 41976.

The previous prime is 64513. The next prime is 64553. The reversal of 64521 is 12546.

It is a happy number.

64521 is a `hidden beast` number, since 645 + 21 = 666.

64521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 64521 - 2³ = 64513 is a prime.

64521 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 64494 and 64503.

It is not an unprimeable number, because it can be changed into a prime (64591) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 550 + ... + 656.

It is an arithmetic number, because the mean of its divisors is an integer number (7956).

2⁶⁴⁵²¹ is an apocalyptic number.

It is an amenable number.

64521 is a deficient number, since it is larger than the sum of its proper divisors (30951).

64521 is a wasteful number, since it uses less digits than its factorization.

64521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180 (or 177 counting only the distinct ones).

The product of its digits is 240, while the sum is 18.

The square root of 64521 is about 254.0098423290. The cubic root of 64521 is about 40.1082484592.

It can be divided in two parts, 645 and 21, that added together give a palindrome (666).

The spelling of 64521 in words is "sixty-four thousand, five hundred twenty-one".