666654456666 has 32 divisors (see below), whose sum is σ = 1493830139328. Its totient is φ = 196556595840.

The previous prime is 666654456647. The next prime is 666654456667.

666654456666 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (66).

It is a junction number, because it is equal to n+sod(n) for n = 666654456597 and 666654456606.

It is not an unprimeable number, because it can be changed into a prime (666654456667) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 136495195 + ... + 136500078.

It is an arithmetic number, because the mean of its divisors is an integer number (46682191854).

Almost surely, 2^666654456666 is an apocalyptic number.

666654456666 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

666654456666 is an abundant number, since it is smaller than the sum of its proper divisors (827175682662).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

666654456666 is a wasteful number, since it uses less digits than its factorization.

666654456666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 272995326.

The product of its digits is 671846400, while the sum is 66.

The spelling of 666654456666 in words is "six hundred sixty-six billion, six hundred fifty-four million, four hundred fifty-six thousand, six hundred sixty-six".