81001111055 has 8 divisors (see below), whose sum is σ = 99572097744. Its totient is φ = 63220379200.

The previous prime is 81001111021. The next prime is 81001111057. The reversal of 81001111055 is 55011110018.

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

It is not a de Polignac number, because 81001111055 - 2⁶ = 81001110991 is a prime.

It is a super-2 number, since 2×81001111055² (a number of 23 digits) contains 22 as substring.

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 81001111055.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81001111057) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 197563481 + ... + 197563890.

It is an arithmetic number, because the mean of its divisors is an integer number (12446512218).

Almost surely, 2^81001111055 is an apocalyptic number.

81001111055 is a deficient number, since it is larger than the sum of its proper divisors (18570986689).

81001111055 is a wasteful number, since it uses less digits than its factorization.

81001111055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 395127417.

The product of its (nonzero) digits is 200, while the sum is 23.

The spelling of 81001111055 in words is "eighty-one billion, one million, one hundred eleven thousand, fifty-five".