221121222210 has 48 divisors (see below), whose sum is σ = 657045919296. Its totient is φ = 50541993504.

The previous prime is 221121222173. The next prime is 221121222221. The reversal of 221121222210 is 12222121122.

It is a happy number.

221121222210 is a `hidden beast` number, since 2 + 211 + 21 + 222 + 210 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 175492404 + ... + 175493663.

It is an arithmetic number, because the mean of its divisors is an integer number (13688456652).

Almost surely, 2^221121222210 is an apocalyptic number.

221121222210 is an abundant number, since it is smaller than the sum of its proper divisors (435924697086).

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

221121222210 is a wasteful number, since it uses less digits than its factorization.

221121222210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 350986087 (or 350986084 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 221121222210 its reverse (12222121122), we get a palindrome (233343343332).

The spelling of 221121222210 in words is "two hundred twenty-one billion, one hundred twenty-one million, two hundred twenty-two thousand, two hundred ten".