211021220221 has 16 divisors (see below), whose sum is σ = 246080674944. Its totient is φ = 177200247744.

The previous prime is 211021220213. The next prime is 211021220227. The reversal of 211021220221 is 122022120112.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 211021220221 - 2³ = 211021220213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 211021220195 and 211021220204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211021220227) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 168915 + ... + 671248.

It is an arithmetic number, because the mean of its divisors is an integer number (15380042184).

Almost surely, 2^211021220221 is an apocalyptic number.

It is an amenable number.

211021220221 is a deficient number, since it is larger than the sum of its proper divisors (35059454723).

211021220221 is an equidigital number, since it uses as much as digits as its factorization.

211021220221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 840900.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 211021220221 its reverse (122022120112), we get a palindrome (333043340333).

The spelling of 211021220221 in words is "two hundred eleven billion, twenty-one million, two hundred twenty thousand, two hundred twenty-one".