166661500001123 has 4 divisors (see below), whose sum is σ = 166661604835440. Its totient is φ = 166661395166808.

The previous prime is 166661500001111. The next prime is 166661500001167. The reversal of 166661500001123 is 321100005166661.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 166661500001123 - 2⁸ = 166661500000867 is a prime.

It is a super-2 number, since 2×166661500001123² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166661500001173) 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, 49995215 + ... + 53224472.

It is an arithmetic number, because the mean of its divisors is an integer number (41665401208860).

Almost surely, 2^{166661500001123} is an apocalyptic number.

166661500001123 is a deficient number, since it is larger than the sum of its proper divisors (104834317).

166661500001123 is a wasteful number, since it uses less digits than its factorization.

166661500001123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104834316.

The product of its (nonzero) digits is 38880, while the sum is 38.

Adding to 166661500001123 its reverse (321100005166661), we get a palindrome (487761505167784).

The spelling of 166661500001123 in words is "one hundred sixty-six trillion, six hundred sixty-one billion, five hundred million, one thousand, one hundred twenty-three".