68905 has 4 divisors (see below), whose sum is σ = 82692. Its totient is φ = 55120.

The previous prime is 68903. The next prime is 68909. The reversal of 68905 is 50986.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 32041 + 36864 = 179^2 + 192^2 .

It is not a de Polignac number, because 68905 - 2¹ = 68903 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6886 + ... + 6895.

It is an arithmetic number, because the mean of its divisors is an integer number (20673).

2⁶⁸⁹⁰⁵ is an apocalyptic number.

It is an amenable number.

68905 is a deficient number, since it is larger than the sum of its proper divisors (13787).

68905 is a wasteful number, since it uses less digits than its factorization.

68905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13786.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 68905 is about 262.4976190368. The cubic root of 68905 is about 40.9968270398.

It can be divided in two parts, 6 and 8905, that added together give a triangular number (8911 = T₁₃₃).

The spelling of 68905 in words is "sixty-eight thousand, nine hundred five".