81510712055 has 16 divisors (see below), whose sum is σ = 98695208160. Its totient is φ = 64620530688.

The previous prime is 81510712051. The next prime is 81510712057. The reversal of 81510712055 is 55021701518.

It is a cyclic number.

It is not a de Polignac number, because 81510712055 - 2² = 81510712051 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81510712051) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5563019 + ... + 5577651.

It is an arithmetic number, because the mean of its divisors is an integer number (6168450510).

Almost surely, 2^81510712055 is an apocalyptic number.

81510712055 is a deficient number, since it is larger than the sum of its proper divisors (17184496105).

81510712055 is a wasteful number, since it uses less digits than its factorization.

81510712055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24610.

The product of its (nonzero) digits is 14000, while the sum is 35.

The spelling of 81510712055 in words is "eighty-one billion, five hundred ten million, seven hundred twelve thousand, fifty-five".