81967316 has 6 divisors (see below), whose sum is σ = 143442810. Its totient is φ = 40983656.

The previous prime is 81967289. The next prime is 81967339. The reversal of 81967316 is 61376918.

It can be written as a sum of positive squares in only one way, i.e., 74891716 + 7075600 = 8654^2 + 2660^2 .

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 10245911 + ... + 10245918.

It is an arithmetic number, because the mean of its divisors is an integer number (23907135).

Almost surely, 2^81967316 is an apocalyptic number.

It is an amenable number.

81967316 is a deficient number, since it is larger than the sum of its proper divisors (61475494).

81967316 is a wasteful number, since it uses less digits than its factorization.

81967316 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20491833 (or 20491831 counting only the distinct ones).

The product of its digits is 54432, while the sum is 41.

The square root of 81967316 is about 9053.5802862735. The cubic root of 81967316 is about 434.3904193481.

The spelling of 81967316 in words is "eighty-one million, nine hundred sixty-seven thousand, three hundred sixteen".