It is an unprimeable number.
121704 is an untouchable number, because it is not equal to the sum of proper divisors of any number.
2121704 is an apocalyptic number.
It is an amenable number.
It is a practical number, because each smaller number is the sum of distinct divisors of 121704, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (166320).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
121704 is a wasteful number, since it uses less digits than its factorization.
121704 is an evil number, because the sum of its binary digits is even.
The square root of 121704 is about 348.8610038396. The cubic root of 121704 is about 49.5566131169.
Adding to 121704 its reverse (407121), we get a palindrome (528825).
The spelling of 121704 in words is "one hundred twenty-one thousand, seven hundred four", and thus it is an iban number.