221021211210 has 16 divisors (see below), whose sum is σ = 530450906976. Its totient is φ = 58938989648.

The previous prime is 221021211161. The next prime is 221021211211. The reversal of 221021211210 is 12112120122.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 221021211210.

It is not an unprimeable number, because it can be changed into a prime (221021211211) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3683686824 + ... + 3683686883.

It is an arithmetic number, because the mean of its divisors is an integer number (33153181686).

Almost surely, 2^221021211210 is an apocalyptic number.

221021211210 is an abundant number, since it is smaller than the sum of its proper divisors (309429695766).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221021211210 is a wasteful number, since it uses less digits than its factorization.

221021211210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7367373717.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 221021211210 its reverse (12112120122), we get a palindrome (233133331332).

The spelling of 221021211210 in words is "two hundred twenty-one billion, twenty-one million, two hundred eleven thousand, two hundred ten".