666618143 has 4 divisors (see below), whose sum is σ = 667037160. Its totient is φ = 666199128.

The previous prime is 666618133. The next prime is 666618179. The reversal of 666618143 is 341816666.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 341816666 = 2 ⋅170908333.

It is a cyclic number.

It is not a de Polignac number, because 666618143 - 2¹⁴ = 666601759 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 666618143.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666618133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 207113 + ... + 210306.

It is an arithmetic number, because the mean of its divisors is an integer number (166759290).

Almost surely, 2^666618143 is an apocalyptic number.

666618143 is a deficient number, since it is larger than the sum of its proper divisors (419017).

666618143 is a wasteful number, since it uses less digits than its factorization.

666618143 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 419016.

The product of its digits is 124416, while the sum is 41.

The square root of 666618143 is about 25818.9493008527. The cubic root of 666618143 is about 873.5592695584.

The spelling of 666618143 in words is "six hundred sixty-six million, six hundred eighteen thousand, one hundred forty-three".