64217645 has 4 divisors (see below), whose sum is σ = 77061180. Its totient is φ = 51374112.

The previous prime is 64217623. The next prime is 64217669. The reversal of 64217645 is 54671246.

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 17732521 + 46485124 = 4211^2 + 6818^2 .

It is a cyclic number.

It is not a de Polignac number, because 64217645 - 2⁸ = 64217389 is a prime.

It is a super-3 number, since 3×64217645³ (a number of 24 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6421760 + ... + 6421769.

It is an arithmetic number, because the mean of its divisors is an integer number (19265295).

Almost surely, 2^64217645 is an apocalyptic number.

It is an amenable number.

64217645 is a deficient number, since it is larger than the sum of its proper divisors (12843535).

64217645 is a wasteful number, since it uses less digits than its factorization.

64217645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12843534.

The product of its digits is 40320, while the sum is 35.

The square root of 64217645 is about 8013.5912673408. The cubic root of 64217645 is about 400.4529140619.

The spelling of 64217645 in words is "sixty-four million, two hundred seventeen thousand, six hundred forty-five".