221001221220210 has 24 divisors (see below), whose sum is σ = 574603175172780. Its totient is φ = 58933658992032.

The previous prime is 221001221220193. The next prime is 221001221220217. The reversal of 221001221220210 is 12022122100122.

It is a happy number.

221001221220210 is a `hidden beast` number, since 2 + 2 + 10 + 0 + 1 + 221 + 220 + 210 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 213841224602721 + 7159996617489 = 14623311^2 + 2675817^2 .

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

It is not an unprimeable number, because it can be changed into a prime (221001221220217) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1227784562245 + ... + 1227784562424.

Almost surely, 2^{221001221220210} is an apocalyptic number.

221001221220210 is an abundant number, since it is smaller than the sum of its proper divisors (353601953952570).

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

221001221220210 is a wasteful number, since it uses less digits than its factorization.

221001221220210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2455569124682 (or 2455569124679 counting only the distinct ones).

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

Adding to 221001221220210 its reverse (12022122100122), we get a palindrome (233023343320332).

The spelling of 221001221220210 in words is "two hundred twenty-one trillion, one billion, two hundred twenty-one million, two hundred twenty thousand, two hundred ten".