81103971 has 16 divisors (see below), whose sum is σ = 116953760. Its totient is φ = 49697280.

The previous prime is 81103927. The next prime is 81103987. The reversal of 81103971 is 17930118.

It is not a de Polignac number, because 81103971 - 2¹⁰ = 81102947 is a prime.

It is a super-2 number, since 2×81103971² = 13155708223937682, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81105971) 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, 5085 + ... + 13713.

It is an arithmetic number, because the mean of its divisors is an integer number (7309610).

Almost surely, 2^81103971 is an apocalyptic number.

81103971 is a deficient number, since it is larger than the sum of its proper divisors (35849789).

81103971 is a wasteful number, since it uses less digits than its factorization.

81103971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8886.

The product of its (nonzero) digits is 1512, while the sum is 30.

The square root of 81103971 is about 9005.7743142941. The cubic root of 81103971 is about 432.8599180263.

The spelling of 81103971 in words is "eighty-one million, one hundred three thousand, nine hundred seventy-one".