66517139 has 8 divisors (see below), whose sum is σ = 72199680. Its totient is φ = 60915456.

The previous prime is 66517133. The next prime is 66517147. The reversal of 66517139 is 93171566.

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 66517139 - 2⁴ = 66517123 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66517133) 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, 18494 + ... + 21795.

It is an arithmetic number, because the mean of its divisors is an integer number (9024960).

Almost surely, 2^66517139 is an apocalyptic number.

66517139 is a deficient number, since it is larger than the sum of its proper divisors (5682541).

66517139 is a wasteful number, since it uses less digits than its factorization.

66517139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40429.

The product of its digits is 34020, while the sum is 38.

The square root of 66517139 is about 8155.8040069634. The cubic root of 66517139 is about 405.1767536161.

The spelling of 66517139 in words is "sixty-six million, five hundred seventeen thousand, one hundred thirty-nine".