16108681 has 4 divisors (see below), whose sum is σ = 16175764. Its totient is φ = 16041600.

The previous prime is 16108679. The next prime is 16108699. The reversal of 16108681 is 18680161.

16108681 = 129² + 130² + ... + 369².

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18680161 = 17 ⋅1098833.

It can be written as a sum of positive squares in 2 ways, for example, as 8732025 + 7376656 = 2955^2 + 2716^2 .

It is a cyclic number.

It is not a de Polignac number, because 16108681 - 2¹ = 16108679 is a prime.

It is a super-2 number, since 2×16108681² = 518979207119522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16108621) by changing a digit.

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, 33180 + ... + 33661.

It is an arithmetic number, because the mean of its divisors is an integer number (4043941).

Almost surely, 2^16108681 is an apocalyptic number.

It is an amenable number.

16108681 is a deficient number, since it is larger than the sum of its proper divisors (67083).

16108681 is an equidigital number, since it uses as much as digits as its factorization.

16108681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67082.

The product of its (nonzero) digits is 2304, while the sum is 31.

The square root of 16108681 is about 4013.5621335666. The cubic root of 16108681 is about 252.5534625219.

The spelling of 16108681 in words is "sixteen million, one hundred eight thousand, six hundred eighty-one".