1020221220221 has 6 divisors (see below), whose sum is σ = 1186787950110. Its totient is φ = 874475331576.

The previous prime is 1020221220217. The next prime is 1020221220223. The reversal of 1020221220221 is 1220221220201.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 589079275225 + 431141944996 = 767515^2 + 656614^2 .

It is not a de Polignac number, because 1020221220221 - 2² = 1020221220217 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1020221220221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1020221220223) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 10410420566 + ... + 10410420663.

It is an arithmetic number, because the mean of its divisors is an integer number (197797991685).

Almost surely, 2^{1020221220221} is an apocalyptic number.

It is an amenable number.

1020221220221 is a deficient number, since it is larger than the sum of its proper divisors (166566729889).

1020221220221 is an equidigital number, since it uses as much as digits as its factorization.

1020221220221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20820841243 (or 20820841236 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 1020221220221 its reverse (1220221220201), we get a palindrome (2240442440422).

The spelling of 1020221220221 in words is "one trillion, twenty billion, two hundred twenty-one million, two hundred twenty thousand, two hundred twenty-one".