2142221 has 4 divisors (see below), whose sum is σ = 2268252. Its totient is φ = 2016192.

The previous prime is 2142211. The next prime is 2142227. The reversal of 2142221 is 1222412.

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 784996 + 1357225 = 886^2 + 1165^2 .

It is a cyclic number.

It is not a de Polignac number, because 2142221 - 2¹⁰ = 2141197 is a prime.

It is a super-2 number, since 2×2142221² = 9178221625682, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2142196 and 2142205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2142227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 62990 + ... + 63023.

It is an arithmetic number, because the mean of its divisors is an integer number (567063).

2^2142221 is an apocalyptic number.

It is an amenable number.

2142221 is a deficient number, since it is larger than the sum of its proper divisors (126031).

2142221 is a wasteful number, since it uses less digits than its factorization.

2142221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126030.

The product of its digits is 64, while the sum is 14.

The square root of 2142221 is about 1463.6328091431. The cubic root of 2142221 is about 128.9104400095.

Adding to 2142221 its reverse (1222412), we get a palindrome (3364633).

The spelling of 2142221 in words is "two million, one hundred forty-two thousand, two hundred twenty-one".