666345808543666 has 8 divisors (see below), whose sum is σ = 1052124960858480. Its totient is φ = 315637488257508.

The previous prime is 666345808543633. The next prime is 666345808543703.

666345808543666 is nontrivially palindromic in base 10.

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

It is a junction number, because it is equal to n+sod(n) for n = 666345808543592 and 666345808543601.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8767708007116 + ... + 8767708007191.

It is an arithmetic number, because the mean of its divisors is an integer number (131515620107310).

Almost surely, 2^{666345808543666} is an apocalyptic number.

666345808543666 is a deficient number, since it is larger than the sum of its proper divisors (385779152314814).

666345808543666 is a wasteful number, since it uses less digits than its factorization.

666345808543666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17535416014328.

The product of its (nonzero) digits is 10749542400, while the sum is 76.

The spelling of 666345808543666 in words is "six hundred sixty-six trillion, three hundred forty-five billion, eight hundred eight million, five hundred forty-three thousand, six hundred sixty-six".