81322318 has 32 divisors (see below), whose sum is σ = 160093440. Its totient is φ = 30015360.

The previous prime is 81322313. The next prime is 81322357.

81322318 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×81322318² = 13226638809786248, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81322313) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10971 + ... + 16822.

It is an arithmetic number, because the mean of its divisors is an integer number (5002920).

Almost surely, 2^81322318 is an apocalyptic number.

81322318 is a deficient number, since it is larger than the sum of its proper divisors (78771122).

81322318 is a wasteful number, since it uses less digits than its factorization.

81322318 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27832.

The product of its digits is 2304, while the sum is 28.

The square root of 81322318 is about 9017.8887773137. Note that the first 3 decimals coincide. The cubic root of 81322318 is about 433.2480164711.

The spelling of 81322318 in words is "eighty-one million, three hundred twenty-two thousand, three hundred eighteen".