81366055 has 8 divisors (see below), whose sum is σ = 97743744. Its totient is φ = 65023200.

The previous prime is 81366053. The next prime is 81366067. The reversal of 81366055 is 55066318.

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

It is not a de Polignac number, because 81366055 - 2¹ = 81366053 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81366055.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81366053) 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 7 ways as a sum of consecutive naturals, for example, 3256 + ... + 13165.

It is an arithmetic number, because the mean of its divisors is an integer number (12217968).

Almost surely, 2^81366055 is an apocalyptic number.

81366055 is a deficient number, since it is larger than the sum of its proper divisors (16377689).

81366055 is a wasteful number, since it uses less digits than its factorization.

81366055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17417.

The product of its (nonzero) digits is 21600, while the sum is 34.

The square root of 81366055 is about 9020.3134646197. The cubic root of 81366055 is about 433.3256727771.

The spelling of 81366055 in words is "eighty-one million, three hundred sixty-six thousand, fifty-five".