64445666 has 4 divisors (see below), whose sum is σ = 96668502. Its totient is φ = 32222832.

The previous prime is 64445653. The next prime is 64445669. The reversal of 64445666 is 66654446.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 38180041 + 26265625 = 6179^2 + 5125^2 .

It is not an unprimeable number, because it can be changed into a prime (64445669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16111415 + ... + 16111418.

Almost surely, 2^64445666 is an apocalyptic number.

64445666 is a deficient number, since it is larger than the sum of its proper divisors (32222836).

64445666 is a wasteful number, since it uses less digits than its factorization.

64445666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32222835.

The product of its digits is 414720, while the sum is 41.

The square root of 64445666 is about 8027.8058023348. The cubic root of 64445666 is about 400.9263239871.

The spelling of 64445666 in words is "sixty-four million, four hundred forty-five thousand, six hundred sixty-six".