64985666 has 4 divisors (see below), whose sum is σ = 97478502. Its totient is φ = 32492832.

The previous prime is 64985663. The next prime is 64985671. The reversal of 64985666 is 66658946.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 66658946 = 2 ⋅33329473.

It can be written as a sum of positive squares in only one way, i.e., 62078641 + 2907025 = 7879^2 + 1705^2 .

It is a super-3 number, since 3×64985666³ (a number of 24 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (64985663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16246415 + ... + 16246418.

Almost surely, 2^64985666 is an apocalyptic number.

64985666 is a deficient number, since it is larger than the sum of its proper divisors (32492836).

64985666 is a wasteful number, since it uses less digits than its factorization.

64985666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32492835.

The product of its digits is 1866240, while the sum is 50.

The square root of 64985666 is about 8061.3687423415. The cubic root of 64985666 is about 402.0430182589.

The spelling of 64985666 in words is "sixty-four million, nine hundred eighty-five thousand, six hundred sixty-six".