72686 has 4 divisors (see below), whose sum is σ = 109032. Its totient is φ = 36342.

The previous prime is 72679. The next prime is 72689. The reversal of 72686 is 68627.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 68627 = 13 ⋅5279.

It is an Ulam number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72689) by changing a digit.

72686 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 (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18170 + ... + 18173.

It is an arithmetic number, because the mean of its divisors is an integer number (27258).

2⁷²⁶⁸⁶ is an apocalyptic number.

72686 is a deficient number, since it is larger than the sum of its proper divisors (36346).

72686 is a wasteful number, since it uses less digits than its factorization.

72686 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36345.

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

The square root of 72686 is about 269.6034124413. The cubic root of 72686 is about 41.7333828954.

The spelling of 72686 in words is "seventy-two thousand, six hundred eighty-six".