1021221203221 has 8 divisors (see below), whose sum is σ = 1056971233080. Its totient is φ = 985506873792.

The previous prime is 1021221203159. The next prime is 1021221203231. The reversal of 1021221203221 is 1223021221201.

It can be written as a sum of positive squares in 4 ways, for example, as 138540284100 + 882680919121 = 372210^2 + 939511^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1021221203221 - 2⁹ = 1021221202709 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021221203231) 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, 8866890 + ... + 8981323.

It is an arithmetic number, because the mean of its divisors is an integer number (132121404135).

Almost surely, 2^{1021221203221} is an apocalyptic number.

It is an amenable number.

1021221203221 is a deficient number, since it is larger than the sum of its proper divisors (35750029859).

1021221203221 is a wasteful number, since it uses less digits than its factorization.

1021221203221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17850215.

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 1021221203221 its reverse (1223021221201), we get a palindrome (2244242424422).

The spelling of 1021221203221 in words is "one trillion, twenty-one billion, two hundred twenty-one million, two hundred three thousand, two hundred twenty-one".