166165510006666 has 32 divisors (see below), whose sum is σ = 264043009161360. Its totient is φ = 78156108496896.

The previous prime is 166165510006637. The next prime is 166165510006669. The reversal of 166165510006666 is 666600015561661.

It can be written as a sum of positive squares in 8 ways, for example, as 112091238909225 + 54074271097441 = 10587315^2 + 7353521^2 .

It is a super-2 number, since 2×166165510006666² (a number of 29 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (166165510006669) 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, 970683130 + ... + 970854298.

Almost surely, 2^{166165510006666} is an apocalyptic number.

166165510006666 is a deficient number, since it is larger than the sum of its proper divisors (97877499154694).

166165510006666 is a wasteful number, since it uses less digits than its factorization.

166165510006666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185418.

The product of its (nonzero) digits is 6998400, while the sum is 55.

The spelling of 166165510006666 in words is "one hundred sixty-six trillion, one hundred sixty-five billion, five hundred ten million, six thousand, six hundred sixty-six".