81285118 has 8 divisors (see below), whose sum is σ = 123067512. Its totient is φ = 40262616.

The previous prime is 81285101. The next prime is 81285121. The reversal of 81285118 is 81158218.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 189705 + ... + 190132.

It is an arithmetic number, because the mean of its divisors is an integer number (15383439).

Almost surely, 2^81285118 is an apocalyptic number.

81285118 is a deficient number, since it is larger than the sum of its proper divisors (41782394).

81285118 is a wasteful number, since it uses less digits than its factorization.

81285118 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 379946.

The product of its digits is 5120, while the sum is 34.

The square root of 81285118 is about 9015.8259743631. The cubic root of 81285118 is about 433.1819448820.

The spelling of 81285118 in words is "eighty-one million, two hundred eighty-five thousand, one hundred eighteen".