64528221 has 8 divisors (see below), whose sum is σ = 86125984. Its totient is φ = 42974640.

The previous prime is 64528213. The next prime is 64528249. The reversal of 64528221 is 12282546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 64528221 - 2³ = 64528213 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64528291) 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 7 ways as a sum of consecutive naturals, for example, 7471 + ... + 13596.

It is an arithmetic number, because the mean of its divisors is an integer number (10765748).

Almost surely, 2^64528221 is an apocalyptic number.

It is an amenable number.

64528221 is a deficient number, since it is larger than the sum of its proper divisors (21597763).

64528221 is a wasteful number, since it uses less digits than its factorization.

64528221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22091.

The product of its digits is 7680, while the sum is 30.

The square root of 64528221 is about 8032.9459726803. The cubic root of 64528221 is about 401.0974466899.

The spelling of 64528221 in words is "sixty-four million, five hundred twenty-eight thousand, two hundred twenty-one".