64565257 has 4 divisors (see below), whose sum is σ = 64585620. Its totient is φ = 64544896.

The previous prime is 64565251. The next prime is 64565261. The reversal of 64565257 is 75256546.

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 41100921 + 23464336 = 6411^2 + 4844^2 .

It is a cyclic number.

It is not a de Polignac number, because 64565257 - 2¹¹ = 64563209 is a prime.

It is a super-2 number, since 2×64565257² = 8337344822952098, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64565251) by changing a digit.

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, 4288 + ... + 12145.

It is an arithmetic number, because the mean of its divisors is an integer number (16146405).

Almost surely, 2^64565257 is an apocalyptic number.

It is an amenable number.

64565257 is a deficient number, since it is larger than the sum of its proper divisors (20363).

64565257 is a wasteful number, since it uses less digits than its factorization.

64565257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20362.

The product of its digits is 252000, while the sum is 40.

The square root of 64565257 is about 8035.2508983852. The cubic root of 64565257 is about 401.1741686972.

The spelling of 64565257 in words is "sixty-four million, five hundred sixty-five thousand, two hundred fifty-seven".