2011021 has 2 divisors, whose sum is σ = 2011022.
Its totient is φ = 2011020.
The previous prime is 2011019. The next prime is 2011027. The reversal of 2011021 is 1201102.
It is a weak prime.
It can be written as a sum of positive squares in only one way, i.e., 1664100 + 346921 = 1290^2 + 589^2
It is a cyclic number.
It is not a de Polignac number, because 2011021 - 21 = 2011019 is a prime.
Together with 2011019, it forms a pair of twin primes.
It is an Ulam number.
It is a junction number, because it is equal to n+sod(n) for n = 2010995 and 2011013.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (2011027) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1005510 + 1005511.
It is an arithmetic number, because the mean of its divisors is an integer number (1005511).
22011021 is an apocalyptic number.
It is an amenable number.
2011021 is a deficient number, since it is larger than the sum of its proper divisors (1).
2011021 is an equidigital number, since it uses as much as digits as its factorization.
2011021 is an evil number, because the sum of its binary digits is even.
The product of its (nonzero) digits is 4, while the sum is 7.
The square root of 2011021 is about 1418.1047210978.
The cubic root of 2011021 is about 126.2231076924.
Adding to 2011021 its reverse (1201102), we get a palindrome (3212123).
The spelling of 2011021 in words is "two million, eleven thousand, twenty-one".