666337643 has 8 divisors (see below), whose sum is σ = 671190336. Its totient is φ = 661494600.

The previous prime is 666337621. The next prime is 666337663. The reversal of 666337643 is 346733666.

It is a happy number.

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 666337643 - 2¹⁸ = 666075499 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 666337594 and 666337603.

It is not an unprimeable number, because it can be changed into a prime (666337663) 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, 189128 + ... + 192618.

It is an arithmetic number, because the mean of its divisors is an integer number (83898792).

Almost surely, 2^666337643 is an apocalyptic number.

666337643 is a deficient number, since it is larger than the sum of its proper divisors (4852693).

666337643 is a wasteful number, since it uses less digits than its factorization.

666337643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4825.

The product of its digits is 979776, while the sum is 44.

The square root of 666337643 is about 25813.5166724722. The cubic root of 666337643 is about 873.4367267633.

The spelling of 666337643 in words is "six hundred sixty-six million, three hundred thirty-seven thousand, six hundred forty-three".