21020220211 has 2 divisors, whose sum is σ = 21020220212. Its totient is φ = 21020220210.

The previous prime is 21020220167. The next prime is 21020220217. The reversal of 21020220211 is 11202202012.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21020220211 - 2¹³ = 21020212019 is a prime.

It is a super-3 number, since 3×21020220211³ (a number of 32 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21020220191 and 21020220200.

It is not a weakly prime, because it can be changed into another prime (21020220217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510110105 + 10510110106.

It is an arithmetic number, because the mean of its divisors is an integer number (10510110106).

Almost surely, 2^21020220211 is an apocalyptic number.

21020220211 is a deficient number, since it is larger than the sum of its proper divisors (1).

21020220211 is an equidigital number, since it uses as much as digits as its factorization.

21020220211 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21020220211 its reverse (11202202012), we get a palindrome (32222422223).

The spelling of 21020220211 in words is "twenty-one billion, twenty million, two hundred twenty thousand, two hundred eleven".