66643801 has 8 divisors (see below), whose sum is σ = 76221824. Its totient is φ = 57080160.

The previous prime is 66643793. The next prime is 66643807. The reversal of 66643801 is 10834666.

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 66643801 - 2³ = 66643793 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66643807) 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 7 ways as a sum of consecutive naturals, for example, 9556 + ... + 14986.

It is an arithmetic number, because the mean of its divisors is an integer number (9527728).

Almost surely, 2^66643801 is an apocalyptic number.

It is an amenable number.

66643801 is a deficient number, since it is larger than the sum of its proper divisors (9578023).

66643801 is a wasteful number, since it uses less digits than its factorization.

66643801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7191.

The product of its (nonzero) digits is 20736, while the sum is 34.

The square root of 66643801 is about 8163.5654587931. The cubic root of 66643801 is about 405.4337698694.

The spelling of 66643801 in words is "sixty-six million, six hundred forty-three thousand, eight hundred one".