2021213 has 4 divisors (see below), whose sum is σ = 2090940. Its totient is φ = 1951488.

The previous prime is 2021203. The next prime is 2021219. The reversal of 2021213 is 3121202.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1737124 + 284089 = 1318^2 + 533^2 .

It is a cyclic number.

It is not a de Polignac number, because 2021213 - 2⁴ = 2021197 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2021194 and 2021203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2021219) 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, 34820 + ... + 34877.

It is an arithmetic number, because the mean of its divisors is an integer number (522735).

2^2021213 is an apocalyptic number.

It is an amenable number.

2021213 is a deficient number, since it is larger than the sum of its proper divisors (69727).

2021213 is an equidigital number, since it uses as much as digits as its factorization.

2021213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69726.

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 2021213 is about 1421.6937082227. The cubic root of 2021213 is about 126.4359844204.

Subtracting from 2021213 its sum of digits (11), we obtain a palindrome (2021202).

Adding to 2021213 its reverse (3121202), we get a palindrome (5142415).

The spelling of 2021213 in words is "two million, twenty-one thousand, two hundred thirteen".