81887716 has 12 divisors (see below), whose sum is σ = 143398332. Its totient is φ = 40916768.

The previous prime is 81887699. The next prime is 81887723. The reversal of 81887716 is 61778818.

81887716 is nontrivially palindromic in base 16.

It can be written as a sum of positive squares in 2 ways, for example, as 34222500 + 47665216 = 5850^2 + 6904^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1026 + ... + 12838.

It is an arithmetic number, because the mean of its divisors is an integer number (11949861).

Almost surely, 2^81887716 is an apocalyptic number.

It is an amenable number.

81887716 is a deficient number, since it is larger than the sum of its proper divisors (61510616).

81887716 is a wasteful number, since it uses less digits than its factorization.

81887716 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13550 (or 13548 counting only the distinct ones).

The product of its digits is 150528, while the sum is 46.

The square root of 81887716 is about 9049.1831675572. The cubic root of 81887716 is about 434.2497589074.

The spelling of 81887716 in words is "eighty-one million, eight hundred eighty-seven thousand, seven hundred sixteen".