It is a happy number.
10121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.
10121 is an esthetic number in base 10, because in such base its adjacent digits differ by 1.
It is a semiprime because it is the product of two primes.
It is a de Polignac number, because none of the positive numbers 2k-10121 is a prime.
It is an alternating number because its digits alternate between odd and even.
It is a Duffinian number.
It is a plaindrome in base 16.
210121 is an apocalyptic number.
It is an amenable number.
10121 is an equidigital number, since it uses as much as digits as its factorization.
10121 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 378.
The square root of 10121 is about 100.6031808642. The cubic root of 10121 is about 21.6308942913.
Adding to 10121 its reverse (12101), we get a palindrome (22222).
Multiplying 10121 by its reverse (12101), we get a palindrome (122474221).
The spelling of 10121 in words is "ten thousand, one hundred twenty-one", and thus it is an iban number.