20000121 has 16 divisors (see below), whose sum is σ = 27172800.
Its totient is φ = 13083200.
The previous prime is 20000107. The next prime is 20000147. The reversal of 20000121 is 12100002.
Adding to 20000121 its reverse (12100002), we get a palindrome (32100123).
It is a happy number.
It is a cyclic number.
It is not a de Polignac number, because 20000121 - 217 = 19869049 is a prime.
It is not an unprimeable number, because it can be changed into a prime (20000161) 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 15 ways as a sum of consecutive naturals, for example, 44926 + ... + 45368.
It is an arithmetic number, because the mean of its divisors is an integer number (1698300).
Almost surely, 220000121 is an apocalyptic number.
It is an amenable number.
20000121 is a deficient number, since it is larger than the sum of its proper divisors (7172679).
20000121 is a wasteful number, since it uses less digits than its factorization.
20000121 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 696.
The product of its (nonzero) digits is 4, while the sum is 6.
The square root of 20000121 is about 4472.1494831904.
The cubic root of 20000121 is about 271.4423090659.
The spelling of 20000121 in words is "twenty million, one hundred twenty-one", and thus it is an aban number.