81608 has 12 divisors (see below), whose sum is σ = 154545. Its totient is φ = 40400.

The previous prime is 81569. The next prime is 81611. The reversal of 81608 is 80618.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 2 ways, for example, as 56644 + 24964 = 238^2 + 158^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=202.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 81608.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 758 + ... + 858.

2⁸¹⁶⁰⁸ is an apocalyptic number.

It is an amenable number.

81608 is a deficient number, since it is larger than the sum of its proper divisors (72937).

81608 is a wasteful number, since it uses less digits than its factorization.

81608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 208 (or 103 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 23.

The square root of 81608 is about 285.6711395994. The cubic root of 81608 is about 43.3754751116.

Subtracting from 81608 its reverse (80618), we obtain a triangular number (990 = T₄₄).

The spelling of 81608 in words is "eighty-one thousand, six hundred eight".