2121021011 has 4 divisors (see below), whose sum is σ = 2141613552.
Its totient is φ = 2100428472.
The previous prime is 2121020989. The next prime is 2121021013. The reversal of 2121021011 is 1101201212.
Adding to 2121021011 its reverse (1101201212), we get a palindrome (3222222223).
It is a semiprime because it is the product of two primes.
It is a cyclic number.
It is not a de Polignac number, because 2121021011 - 26 = 2121020947 is a prime.
It is a Duffinian number.
It is a junction number, because it is equal to n+sod(n) for n = 2121020983 and 2121021001.
It is not an unprimeable number, because it can be changed into a prime (2121021013) by changing a digit.
It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10296116 + ... + 10296321.
It is an arithmetic number, because the mean of its divisors is an integer number (535403388).
Almost surely, 22121021011 is an apocalyptic number.
2121021011 is a deficient number, since it is larger than the sum of its proper divisors (20592541).
2121021011 is a wasteful number, since it uses less digits than its factorization.
2121021011 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 20592540.
The product of its (nonzero) digits is 8, while the sum is 11.
The square root of 2121021011 is about 46054.5438691993.
The cubic root of 2121021011 is about 1284.8378546538.
The spelling of 2121021011 in words is "two billion, one hundred twenty-one million, twenty-one thousand, eleven".