66606657 has 8 divisors (see below), whose sum is σ = 95640384. Its totient is φ = 40988688.

The previous prime is 66606611. The next prime is 66606667. The reversal of 66606657 is 75660666.

66606657 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 66606657 - 2⁶ = 66606593 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66606667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 853893 + ... + 853970.

It is an arithmetic number, because the mean of its divisors is an integer number (11955048).

Almost surely, 2^66606657 is an apocalyptic number.

It is an amenable number.

66606657 is a deficient number, since it is larger than the sum of its proper divisors (29033727).

66606657 is a wasteful number, since it uses less digits than its factorization.

66606657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1707879.

The product of its (nonzero) digits is 272160, while the sum is 42.

The square root of 66606657 is about 8161.2901553615. The cubic root of 66606657 is about 405.3584328769.

The spelling of 66606657 in words is "sixty-six million, six hundred six thousand, six hundred fifty-seven".