6666663 has 8 divisors (see below), whose sum is σ = 9356800. Its totient is φ = 4210488.

The previous prime is 6666617. The next prime is 6666679. The reversal of 6666663 is 3666666.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 6666663 - 2⁶ = 6666599 is a prime.

It is a Duffinian number.

6666663 is a lucky number.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6666613) 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, 58423 + ... + 58536.

It is an arithmetic number, because the mean of its divisors is an integer number (1169600).

Almost surely, 2^6666663 is an apocalyptic number.

6666663 is a deficient number, since it is larger than the sum of its proper divisors (2690137).

6666663 is a wasteful number, since it uses less digits than its factorization.

6666663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116981.

The product of its digits is 139968, while the sum is 39.

The square root of 6666663 is about 2581.9881874246. The cubic root of 6666663 is about 188.2071712715.

The spelling of 6666663 in words is "six million, six hundred sixty-six thousand, six hundred sixty-three".