66857663 has 8 divisors (see below), whose sum is σ = 67434048. Its totient is φ = 66284064.

The previous prime is 66857627. The next prime is 66857683. The reversal of 66857663 is 36675866.

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 66857663 - 2¹⁰ = 66856639 is a prime.

It is a Duffinian number.

It is a zygodrome in base 4.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66857683) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 90845 + ... + 91577.

It is an arithmetic number, because the mean of its divisors is an integer number (8429256).

Almost surely, 2^66857663 is an apocalyptic number.

66857663 is a deficient number, since it is larger than the sum of its proper divisors (576385).

66857663 is a wasteful number, since it uses less digits than its factorization.

66857663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1393.

The product of its digits is 1088640, while the sum is 47.

The square root of 66857663 is about 8176.6535330782. The cubic root of 66857663 is about 405.8669899251.

The spelling of 66857663 in words is "sixty-six million, eight hundred fifty-seven thousand, six hundred sixty-three".