210211211221 has 32 divisors (see below), whose sum is σ = 243992062080. Its totient is φ = 179095392000.

The previous prime is 210211211201. The next prime is 210211211267. The reversal of 210211211221 is 122112112012.

It is a cyclic number.

It is not a de Polignac number, because 210211211221 - 2⁹ = 210211210709 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 210211211195 and 210211211204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210211211201) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 28979031 + ... + 28986283.

It is an arithmetic number, because the mean of its divisors is an integer number (7624751940).

Almost surely, 2^210211211221 is an apocalyptic number.

It is an amenable number.

210211211221 is a deficient number, since it is larger than the sum of its proper divisors (33780850859).

210211211221 is a wasteful number, since it uses less digits than its factorization.

210211211221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8757.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 210211211221 its reverse (122112112012), we get a palindrome (332323323233).

The spelling of 210211211221 in words is "two hundred ten billion, two hundred eleven million, two hundred eleven thousand, two hundred twenty-one".