81871455 has 16 divisors (see below), whose sum is σ = 133143264. Its totient is φ = 42948480.

The previous prime is 81871423. The next prime is 81871457. The reversal of 81871455 is 55417818.

It is not a de Polignac number, because 81871455 - 2⁵ = 81871423 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81871457) 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 15 ways as a sum of consecutive naturals, for example, 43824 + ... + 45653.

It is an arithmetic number, because the mean of its divisors is an integer number (8321454).

Almost surely, 2^81871455 is an apocalyptic number.

81871455 is a deficient number, since it is larger than the sum of its proper divisors (51271809).

81871455 is a wasteful number, since it uses less digits than its factorization.

81871455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89546.

The product of its digits is 44800, while the sum is 39.

The square root of 81871455 is about 9048.2846440638. The cubic root of 81871455 is about 434.2210130298.

The spelling of 81871455 in words is "eighty-one million, eight hundred seventy-one thousand, four hundred fifty-five".