66643603 has 8 divisors (see below), whose sum is σ = 73297728. Its totient is φ = 60207744.

The previous prime is 66643601. The next prime is 66643607. The reversal of 66643603 is 30634666.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66643603 - 2¹ = 66643601 is a prime.

It is a Duffinian 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 7 ways as a sum of consecutive naturals, for example, 53926 + ... + 55147.

It is an arithmetic number, because the mean of its divisors is an integer number (9162216).

Almost surely, 2^66643603 is an apocalyptic number.

66643603 is a deficient number, since it is larger than the sum of its proper divisors (6654125).

66643603 is a wasteful number, since it uses less digits than its factorization.

66643603 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109133.

The product of its (nonzero) digits is 46656, while the sum is 34.

The square root of 66643603 is about 8163.5533317300. The cubic root of 66643603 is about 405.4333683518.

The spelling of 66643603 in words is "sixty-six million, six hundred forty-three thousand, six hundred three".