72166 has 4 divisors (see below), whose sum is σ = 108252. Its totient is φ = 36082.

The previous prime is 72161. The next prime is 72167. The reversal of 72166 is 66127.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 66127 = 89 ⋅743.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18040 + ... + 18043.

It is an arithmetic number, because the mean of its divisors is an integer number (27063).

2⁷²¹⁶⁶ is an apocalyptic number.

72166 is a deficient number, since it is larger than the sum of its proper divisors (36086).

72166 is a wasteful number, since it uses less digits than its factorization.

72166 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36085.

The product of its digits is 504, while the sum is 22.

The square root of 72166 is about 268.6373019519. The cubic root of 72166 is about 41.6336235804.

It can be divided in two parts, 721 and 66, that multiplied together give a triangular number (47586 = T₃₀₈).

The spelling of 72166 in words is "seventy-two thousand, one hundred sixty-six".