66543799 has 8 divisors (see below), whose sum is σ = 77339520. Its totient is φ = 56070456.

The previous prime is 66543791. The next prime is 66543811. The reversal of 66543799 is 99734566.

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 66543799 - 2³ = 66543791 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66543791) 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, 80149 + ... + 80974.

It is an arithmetic number, because the mean of its divisors is an integer number (9667440).

Almost surely, 2^66543799 is an apocalyptic number.

66543799 is a deficient number, since it is larger than the sum of its proper divisors (10795721).

66543799 is a wasteful number, since it uses less digits than its factorization.

66543799 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161189.

The product of its digits is 1224720, while the sum is 49.

The square root of 66543799 is about 8157.4382621017. The cubic root of 66543799 is about 405.2308778593.

The spelling of 66543799 in words is "sixty-six million, five hundred forty-three thousand, seven hundred ninety-nine".