64446221 has 6 divisors (see below), whose sum is σ = 74968110. Its totient is φ = 55239576.

The previous prime is 64446211. The next prime is 64446223. The reversal of 64446221 is 12264446.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 48804196 + 15642025 = 6986^2 + 3955^2 .

It is not a de Polignac number, because 64446221 - 2¹⁸ = 64184077 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64446223) 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 5 ways as a sum of consecutive naturals, for example, 657566 + ... + 657663.

It is an arithmetic number, because the mean of its divisors is an integer number (12494685).

Almost surely, 2^64446221 is an apocalyptic number.

It is an amenable number.

64446221 is a deficient number, since it is larger than the sum of its proper divisors (10521889).

64446221 is a wasteful number, since it uses less digits than its factorization.

64446221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1315243 (or 1315236 counting only the distinct ones).

The product of its digits is 9216, while the sum is 29.

The square root of 64446221 is about 8027.8403696137. The cubic root of 64446221 is about 400.9274748970.

The spelling of 64446221 in words is "sixty-four million, four hundred forty-six thousand, two hundred twenty-one".