66857443 has 4 divisors (see below), whose sum is σ = 67990680. Its totient is φ = 65724208.

The previous prime is 66857431. The next prime is 66857459. The reversal of 66857443 is 34475866.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34475866 = 2 ⋅17237933.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66857443 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 66857443.

It is not an unprimeable number, because it can be changed into a prime (66857743) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 566530 + ... + 566647.

It is an arithmetic number, because the mean of its divisors is an integer number (16997670).

Almost surely, 2^66857443 is an apocalyptic number.

66857443 is a deficient number, since it is larger than the sum of its proper divisors (1133237).

66857443 is a wasteful number, since it uses less digits than its factorization.

66857443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1133236.

The product of its digits is 483840, while the sum is 43.

The square root of 66857443 is about 8176.6400801307. The cubic root of 66857443 is about 405.8665447463.

The spelling of 66857443 in words is "sixty-six million, eight hundred fifty-seven thousand, four hundred forty-three".