81677271 has 16 divisors (see below), whose sum is σ = 117501440. Its totient is φ = 50168160.

The previous prime is 81677263. The next prime is 81677287. The reversal of 81677271 is 17277618.

It is not a de Polignac number, because 81677271 - 2³ = 81677263 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81677251) by changing a digit.

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, 22950 + ... + 26268.

It is an arithmetic number, because the mean of its divisors is an integer number (7343840).

Almost surely, 2^81677271 is an apocalyptic number.

81677271 is a deficient number, since it is larger than the sum of its proper divisors (35824169).

81677271 is a wasteful number, since it uses less digits than its factorization.

81677271 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3966.

The product of its digits is 32928, while the sum is 39.

The square root of 81677271 is about 9037.5478421970. The cubic root of 81677271 is about 433.8774438577.

It can be divided in two parts, 816 and 77271, that added together give a palindrome (78087).

The spelling of 81677271 in words is "eighty-one million, six hundred seventy-seven thousand, two hundred seventy-one".