81579318 has 16 divisors (see below), whose sum is σ = 163499520. Its totient is φ = 27136296.

The previous prime is 81579317. The next prime is 81579319. The reversal of 81579318 is 81397518.

It is an interprime number because it is at equal distance from previous prime (81579317) and next prime (81579319).

It is a self number, because there is not a number n which added to its sum of digits gives 81579318.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81579313) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11038 + ... + 16881.

It is an arithmetic number, because the mean of its divisors is an integer number (10218720).

Almost surely, 2^81579318 is an apocalyptic number.

81579318 is an abundant number, since it is smaller than the sum of its proper divisors (81920202).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81579318 is a wasteful number, since it uses less digits than its factorization.

81579318 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28411.

The product of its digits is 60480, while the sum is 42.

The square root of 81579318 is about 9032.1269920213. The cubic root of 81579318 is about 433.7039292534.

The spelling of 81579318 in words is "eighty-one million, five hundred seventy-nine thousand, three hundred eighteen".