666912818 has 32 divisors (see below), whose sum is σ = 1177388352. Its totient is φ = 279316800.

The previous prime is 666912811. The next prime is 666912821. The reversal of 666912818 is 818219666.

It is a super-2 number, since 2×666912818² = 889545413625402248, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (666912811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 184973 + ... + 188543.

It is an arithmetic number, because the mean of its divisors is an integer number (36793386).

Almost surely, 2^666912818 is an apocalyptic number.

666912818 is a deficient number, since it is larger than the sum of its proper divisors (510475534).

666912818 is a wasteful number, since it uses less digits than its factorization.

666912818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4250.

The product of its digits is 248832, while the sum is 47.

The square root of 666912818 is about 25824.6552348720. The cubic root of 666912818 is about 873.6879680044.

The spelling of 666912818 in words is "six hundred sixty-six million, nine hundred twelve thousand, eight hundred eighteen".