81571055 has 16 divisors (see below), whose sum is σ = 102556800. Its totient is φ = 62200320.

The previous prime is 81571027. The next prime is 81571069. The reversal of 81571055 is 55017518.

It is a happy number.

It is not a de Polignac number, because 81571055 - 2⁸ = 81570799 is a prime.

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 15 ways as a sum of consecutive naturals, for example, 7895 + ... + 15015.

It is an arithmetic number, because the mean of its divisors is an integer number (6409800).

Almost surely, 2^81571055 is an apocalyptic number.

81571055 is a deficient number, since it is larger than the sum of its proper divisors (20985745).

81571055 is a wasteful number, since it uses less digits than its factorization.

81571055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7234.

The product of its (nonzero) digits is 7000, while the sum is 32.

The square root of 81571055 is about 9031.6695577285. The cubic root of 81571055 is about 433.6892857684.

The spelling of 81571055 in words is "eighty-one million, five hundred seventy-one thousand, fifty-five".