64521365 has 16 divisors (see below), whose sum is σ = 79377408. Its totient is φ = 50324736.

The previous prime is 64521361. The next prime is 64521367. The reversal of 64521365 is 56312546.

It is a cyclic number.

It is not a de Polignac number, because 64521365 - 2² = 64521361 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64521361) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 108509 + ... + 109101.

It is an arithmetic number, because the mean of its divisors is an integer number (4961088).

Almost surely, 2^64521365 is an apocalyptic number.

It is an amenable number.

64521365 is a deficient number, since it is larger than the sum of its proper divisors (14856043).

64521365 is a wasteful number, since it uses less digits than its factorization.

64521365 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1108.

The product of its digits is 21600, while the sum is 32.

The square root of 64521365 is about 8032.5192187756. The cubic root of 64521365 is about 401.0832409081.

The spelling of 64521365 in words is "sixty-four million, five hundred twenty-one thousand, three hundred sixty-five".