81333366 has 8 divisors (see below), whose sum is σ = 162666744. Its totient is φ = 27111120.

The previous prime is 81333361. The next prime is 81333391. The reversal of 81333366 is 66333318.

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

81333366 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81333361) 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 3 ways as a sum of consecutive naturals, for example, 6777775 + ... + 6777786.

It is an arithmetic number, because the mean of its divisors is an integer number (20333343).

Almost surely, 2^81333366 is an apocalyptic number.

81333366 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

81333366 is a wasteful number, since it uses less digits than its factorization.

81333366 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13555566.

The product of its digits is 23328, while the sum is 33.

The square root of 81333366 is about 9018.5013167377. The cubic root of 81333366 is about 433.2676351418.

The spelling of 81333366 in words is "eighty-one million, three hundred thirty-three thousand, three hundred sixty-six".