666660998 has 8 divisors (see below), whose sum is σ = 1004284008. Its totient is φ = 331899664.

The previous prime is 666660991. The next prime is 666661007. The reversal of 666660998 is 899066666.

666660998 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666660991) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 714836 + ... + 715767.

It is an arithmetic number, because the mean of its divisors is an integer number (125535501).

Almost surely, 2^666660998 is an apocalyptic number.

666660998 is a deficient number, since it is larger than the sum of its proper divisors (337623010).

666660998 is a wasteful number, since it uses less digits than its factorization.

666660998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1430838.

The product of its (nonzero) digits is 5038848, while the sum is 56.

The square root of 666660998 is about 25819.7792012248. The cubic root of 666660998 is about 873.5779887111.

The spelling of 666660998 in words is "six hundred sixty-six million, six hundred sixty thousand, nine hundred ninety-eight".