2011221 has 6 divisors (see below), whose sum is σ = 2905110. Its totient is φ = 1340808.

The previous prime is 2011211. The next prime is 2011241. The reversal of 2011221 is 1221102.

It can be written as a sum of positive squares in only one way, i.e., 1535121 + 476100 = 1239^2 + 690^2 .

It is not a de Polignac number, because 2011221 - 2¹¹ = 2009173 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 223469 = 2011221 / (2 + 0 + 1 + 1 + 2 + 2 + 1).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2011201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 111726 + ... + 111743.

It is an arithmetic number, because the mean of its divisors is an integer number (484185).

2^2011221 is an apocalyptic number.

It is an amenable number.

2011221 is a deficient number, since it is larger than the sum of its proper divisors (893889).

2011221 is a wasteful number, since it uses less digits than its factorization.

2011221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 223475 (or 223472 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 2011221 is about 1418.1752359987. The cubic root of 2011221 is about 126.2272919326.

Adding to 2011221 its reverse (1221102), we get a palindrome (3232323).

The spelling of 2011221 in words is "two million, eleven thousand, two hundred twenty-one".