64320221 has 4 divisors (see below), whose sum is σ = 73508832. Its totient is φ = 55131612.

The previous prime is 64320209. The next prime is 64320229. The reversal of 64320221 is 12202346.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 64320221 - 2¹⁸ = 64058077 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 64320193 and 64320202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64320229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4594295 + ... + 4594308.

It is an arithmetic number, because the mean of its divisors is an integer number (18377208).

Almost surely, 2^64320221 is an apocalyptic number.

It is an amenable number.

64320221 is a deficient number, since it is larger than the sum of its proper divisors (9188611).

64320221 is an equidigital number, since it uses as much as digits as its factorization.

64320221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9188610.

The product of its (nonzero) digits is 576, while the sum is 20.

The square root of 64320221 is about 8019.9888403912. The cubic root of 64320221 is about 400.6660175195. Note that the first 3 decimals are identical.

Adding to 64320221 its reverse (12202346), we get a palindrome (76522567).

The spelling of 64320221 in words is "sixty-four million, three hundred twenty thousand, two hundred twenty-one".