72866 has 4 divisors (see below), whose sum is σ = 109302. Its totient is φ = 36432.

The previous prime is 72859. The next prime is 72869. The reversal of 72866 is 66827.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 66827 = 17 ⋅3931.

It can be written as a sum of positive squares in only one way, i.e., 48841 + 24025 = 221^2 + 155^2 .

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 72866.

It is not an unprimeable number, because it can be changed into a prime (72869) by changing a digit.

72866 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18215 + ... + 18218.

2⁷²⁸⁶⁶ is an apocalyptic number.

72866 is a deficient number, since it is larger than the sum of its proper divisors (36436).

72866 is a wasteful number, since it uses less digits than its factorization.

72866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36435.

The product of its digits is 4032, while the sum is 29.

The square root of 72866 is about 269.9370296940. The cubic root of 72866 is about 41.7678040885.

The spelling of 72866 in words is "seventy-two thousand, eight hundred sixty-six".