2121200001 has 16 divisors (see below), whose sum is σ = 3279150720.
Its totient is φ = 1352648880.
The previous prime is 2121199999. The next prime is 2121200021. The reversal of 2121200001 is 1000021212.
It is not a de Polignac number, because 2121200001 - 21 = 2121199999 is a prime.
It is a Harshad number since it is a multiple of its sum of digits (9).
It is not an unprimeable number, because it can be changed into a prime (2121200021) by changing a digit.
It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1707270 + ... + 1708511.
It is an arithmetic number, because the mean of its divisors is an integer number (204946920).
Almost surely, 22121200001 is an apocalyptic number.
It is an amenable number.
2121200001 is a deficient number, since it is larger than the sum of its proper divisors (1157950719).
2121200001 is a wasteful number, since it uses less digits than its factorization.
2121200001 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 3415813 (or 3415807 counting only the distinct ones).
The product of its (nonzero) digits is 8, while the sum is 9.
The square root of 2121200001 is about 46056.4870675131.
The cubic root of 2121200001 is about 1284.8739955277.
Adding to 2121200001 its reverse (1000021212), we get a palindrome (3121221213).
The spelling of 2121200001 in words is "two billion, one hundred twenty-one million, two hundred thousand, one".