Adding to 39858 its reverse (85893), we get a triangular number (125751 = T501).
39858 is nontrivially palindromic in base 9.
39858 is an undulating number in base 9.
239858 is an apocalyptic number.
It is a practical number, because each smaller number is the sum of distinct divisors of 39858, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49728).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
39858 is a wasteful number, since it uses less digits than its factorization.
39858 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 98.
The square root of 39858 is about 199.6446843770. The cubic root of 39858 is about 34.1590015193.
The spelling of 39858 in words is "thirty-nine thousand, eight hundred fifty-eight".