81355318 has 24 divisors (see below), whose sum is σ = 136687824. Its totient is φ = 36276240.

The previous prime is 81355297. The next prime is 81355331.

81355318 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×81355318² = 13237375533762248, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 9655 + ... + 15997.

It is an arithmetic number, because the mean of its divisors is an integer number (5695326).

Almost surely, 2^81355318 is an apocalyptic number.

81355318 is a deficient number, since it is larger than the sum of its proper divisors (55332506).

81355318 is a wasteful number, since it uses less digits than its factorization.

81355318 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6420 (or 6409 counting only the distinct ones).

The product of its digits is 14400, while the sum is 34.

The square root of 81355318 is about 9019.7182882837. The cubic root of 81355318 is about 433.3066115015.

The spelling of 81355318 in words is "eighty-one million, three hundred fifty-five thousand, three hundred eighteen".