81207 has 12 divisors (see below), whose sum is σ = 134160. Its totient is φ = 46368.

The previous prime is 81203. The next prime is 81223. The reversal of 81207 is 70218.

It is not a de Polignac number, because 81207 - 2² = 81203 is a prime.

81207 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 81207.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 81207.

It is not an unprimeable number, because it can be changed into a prime (81203) by changing a digit.

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 in 11 ways as a sum of consecutive naturals, for example, 582 + ... + 707.

It is an arithmetic number, because the mean of its divisors is an integer number (11180).

2⁸¹²⁰⁷ is an apocalyptic number.

81207 is a deficient number, since it is larger than the sum of its proper divisors (52953).

81207 is a wasteful number, since it uses less digits than its factorization.

81207 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1302 (or 1299 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 18.

The square root of 81207 is about 284.9684193029. The cubic root of 81207 is about 43.3043132456.

Adding to 81207 its sum of digits (18), we get a square (81225 = 285²).

The spelling of 81207 in words is "eighty-one thousand, two hundred seven".