81871039 has 8 divisors (see below), whose sum is σ = 84104640. Its totient is φ = 79658016.

The previous prime is 81871021. The next prime is 81871043. The reversal of 81871039 is 93017818.

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

It is a cyclic number.

It is not a de Polignac number, because 81871039 - 2¹⁷ = 81739967 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81870989 and 81871007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81871739) 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, 3097 + ... + 13165.

It is an arithmetic number, because the mean of its divisors is an integer number (10513080).

Almost surely, 2^81871039 is an apocalyptic number.

81871039 is a deficient number, since it is larger than the sum of its proper divisors (2233601).

81871039 is a wasteful number, since it uses less digits than its factorization.

81871039 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10289.

The product of its (nonzero) digits is 12096, while the sum is 37.

The square root of 81871039 is about 9048.2616562520. The cubic root of 81871039 is about 434.2202775832.

The spelling of 81871039 in words is "eighty-one million, eight hundred seventy-one thousand, thirty-nine".