221221101213210 has 48 divisors (see below), whose sum is σ = 617613196860576. Its totient is φ = 50564823134112.

The previous prime is 221221101213209. The next prime is 221221101213293. The reversal of 221221101213210 is 12312101122122.

It is a Harshad number since it is a multiple of its sum of digits (21).

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, 75245271052 + ... + 75245273991.

It is an arithmetic number, because the mean of its divisors is an integer number (12866941601262).

Almost surely, 2^{221221101213210} is an apocalyptic number.

221221101213210 is an abundant number, since it is smaller than the sum of its proper divisors (396392095647366).

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

221221101213210 is a wasteful number, since it uses less digits than its factorization.

221221101213210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150490545067 (or 150490545060 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 21.

Adding to 221221101213210 its reverse (12312101122122), we get a palindrome (233533202335332).

The spelling of 221221101213210 in words is "two hundred twenty-one trillion, two hundred twenty-one billion, one hundred one million, two hundred thirteen thousand, two hundred ten".