166643011 has 4 divisors (see below), whose sum is σ = 172018624. Its totient is φ = 161267400.

The previous prime is 166642999. The next prime is 166643041. The reversal of 166643011 is 110346661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 110346661 = 19 ⋅5807719.

It is a cyclic number.

It is not a de Polignac number, because 166643011 - 2¹⁵ = 166610243 is a prime.

It is a super-2 number, since 2×166643011² = 55539786230292242, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166643041) 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, 2687760 + ... + 2687821.

It is an arithmetic number, because the mean of its divisors is an integer number (43004656).

Almost surely, 2^166643011 is an apocalyptic number.

166643011 is a deficient number, since it is larger than the sum of its proper divisors (5375613).

166643011 is an equidigital number, since it uses as much as digits as its factorization.

166643011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5375612.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 166643011 is about 12909.0282748160. The cubic root of 166643011 is about 550.2951704871.

Adding to 166643011 its reverse (110346661), we get a palindrome (276989672).

The spelling of 166643011 in words is "one hundred sixty-six million, six hundred forty-three thousand, eleven".