81910316 has 12 divisors (see below), whose sum is σ = 143628240. Its totient is φ = 40873680.

The previous prime is 81910303. The next prime is 81910321. The reversal of 81910316 is 61301918.

It is a happy 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 in 3 ways as a sum of consecutive naturals, for example, 18080 + ... + 22151.

It is an arithmetic number, because the mean of its divisors is an integer number (11969020).

Almost surely, 2^81910316 is an apocalyptic number.

It is an amenable number.

81910316 is a deficient number, since it is larger than the sum of its proper divisors (61717924).

81910316 is a wasteful number, since it uses less digits than its factorization.

81910316 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40744 (or 40742 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 29.

The square root of 81910316 is about 9050.4318129026. The cubic root of 81910316 is about 434.2897044260.

The spelling of 81910316 in words is "eighty-one million, nine hundred ten thousand, three hundred sixteen".