64520305 has 4 divisors (see below), whose sum is σ = 77424372. Its totient is φ = 51616240.

The previous prime is 64520297. The next prime is 64520311. The reversal of 64520305 is 50302546.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7306209 + 57214096 = 2703^2 + 7564^2 .

It is not a de Polignac number, because 64520305 - 2³ = 64520297 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 64520305.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6452026 + ... + 6452035.

It is an arithmetic number, because the mean of its divisors is an integer number (19356093).

Almost surely, 2^64520305 is an apocalyptic number.

It is an amenable number.

64520305 is a deficient number, since it is larger than the sum of its proper divisors (12904067).

64520305 is a wasteful number, since it uses less digits than its factorization.

64520305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12904066.

The product of its (nonzero) digits is 3600, while the sum is 25.

The square root of 64520305 is about 8032.4532367142. The cubic root of 64520305 is about 401.0810444751.

The spelling of 64520305 in words is "sixty-four million, five hundred twenty thousand, three hundred five".