66643608 has 16 divisors (see below), whose sum is σ = 166609080. Its totient is φ = 22214528.

The previous prime is 66643607. The next prime is 66643609. The reversal of 66643608 is 80634666.

It is an interprime number because it is at equal distance from previous prime (66643607) and next prime (66643609).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66643601) 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, 1388385 + ... + 1388432.

Almost surely, 2^66643608 is an apocalyptic number.

It is an amenable number.

66643608 is an abundant number, since it is smaller than the sum of its proper divisors (99965472).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66643608 is a wasteful number, since it uses less digits than its factorization.

66643608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2776826 (or 2776822 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 39.

The square root of 66643608 is about 8163.5536379692. The cubic root of 66643608 is about 405.4333784912.

The spelling of 66643608 in words is "sixty-six million, six hundred forty-three thousand, six hundred eight".