2120221 has 2 divisors, whose sum is σ = 2120222. Its totient is φ = 2120220.

The previous prime is 2120213. The next prime is 2120227. The reversal of 2120221 is 1220212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1092025 + 1028196 = 1045^2 + 1014^2 .

It is a cyclic number.

It is not a de Polignac number, because 2120221 - 2³ = 2120213 is a prime.

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 2120198 and 2120207.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2120227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060110 + 1060111.

It is an arithmetic number, because the mean of its divisors is an integer number (1060111).

2^2120221 is an apocalyptic number.

It is an amenable number.

2120221 is a deficient number, since it is larger than the sum of its proper divisors (1).

2120221 is an equidigital number, since it uses as much as digits as its factorization.

2120221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 2120221 is about 1456.0978675900. The cubic root of 2120221 is about 128.4676295092.

Adding to 2120221 its reverse (1220212), we get a palindrome (3340433).

Subtracting from 2120221 its reverse (1220212), we obtain a palindrome (900009).

The spelling of 2120221 in words is "two million, one hundred twenty thousand, two hundred twenty-one".