666577166120 has 64 divisors (see below), whose sum is σ = 1527721851600. Its totient is φ = 261710479360.

The previous prime is 666577166111. The next prime is 666577166153. The reversal of 666577166120 is 21661775666.

It can be written as a sum of positive squares in 8 ways, for example, as 330963186436 + 335613979684 = 575294^2 + 579322^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 195641 + ... + 1171080.

Almost surely, 2^666577166120 is an apocalyptic number.

It is an amenable number.

666577166120 is an abundant number, since it is smaller than the sum of its proper divisors (861144685480).

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

666577166120 is a wasteful number, since it uses less digits than its factorization.

666577166120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1366958 (or 1366954 counting only the distinct ones).

The product of its (nonzero) digits is 3810240, while the sum is 53.

The spelling of 666577166120 in words is "six hundred sixty-six billion, five hundred seventy-seven million, one hundred sixty-six thousand, one hundred twenty".