166611616506091 has 8 divisors (see below), whose sum is σ = 175715984813120. Its totient is φ = 157540781785032.

The previous prime is 166611616506067. The next prime is 166611616506109. The reversal of 166611616506091 is 190605616116661.

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

It is a cyclic number.

It is not a de Polignac number, because 166611616506091 - 2⁷ = 166611616505963 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166611616506791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8383386285 + ... + 8383406158.

It is an arithmetic number, because the mean of its divisors is an integer number (21964498101640).

Almost surely, 2^{166611616506091} is an apocalyptic number.

166611616506091 is a deficient number, since it is larger than the sum of its proper divisors (9104368307029).

166611616506091 is a wasteful number, since it uses less digits than its factorization.

166611616506091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16766792985.

The product of its (nonzero) digits is 2099520, while the sum is 55.

The spelling of 166611616506091 in words is "one hundred sixty-six trillion, six hundred eleven billion, six hundred sixteen million, five hundred six thousand, ninety-one".