64652221 has 4 divisors (see below), whose sum is σ = 65292444. Its totient is φ = 64012000.

The previous prime is 64652219. The next prime is 64652239. The reversal of 64652221 is 12225646.

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 63824121 + 828100 = 7989^2 + 910^2 .

It is a cyclic number.

It is not a de Polignac number, because 64652221 - 2¹ = 64652219 is a prime.

It is a super-3 number, since 3×64652221³ (a number of 24 digits) contains 333 as substring.

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 64652221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64652201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 319960 + ... + 320161.

It is an arithmetic number, because the mean of its divisors is an integer number (16323111).

Almost surely, 2^64652221 is an apocalyptic number.

It is an amenable number.

64652221 is a deficient number, since it is larger than the sum of its proper divisors (640223).

64652221 is a wasteful number, since it uses less digits than its factorization.

64652221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 640222.

The product of its digits is 5760, while the sum is 28.

The square root of 64652221 is about 8040.6604828210. The cubic root of 64652221 is about 401.3542039056.

Adding to 64652221 its reverse (12225646), we get a palindrome (76877867).

The spelling of 64652221 in words is "sixty-four million, six hundred fifty-two thousand, two hundred twenty-one".