1031221310221 has 4 divisors (see below), whose sum is σ = 1036564426012. Its totient is φ = 1025878194432.

The previous prime is 1031221310201. The next prime is 1031221310237. The reversal of 1031221310221 is 1220131221301.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 430191692100 + 601029618121 = 655890^2 + 775261^2 .

It is a cyclic number.

It is not a de Polignac number, because 1031221310221 - 2¹³ = 1031221302029 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 (1031221310201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2671557606 + ... + 2671557991.

It is an arithmetic number, because the mean of its divisors is an integer number (259141106503).

Almost surely, 2^{1031221310221} is an apocalyptic number.

It is an amenable number.

1031221310221 is a deficient number, since it is larger than the sum of its proper divisors (5343115791).

1031221310221 is an equidigital number, since it uses as much as digits as its factorization.

1031221310221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5343115790.

The product of its (nonzero) digits is 144, while the sum is 19.

Adding to 1031221310221 its reverse (1220131221301), we get a palindrome (2251352531522).

The spelling of 1031221310221 in words is "one trillion, thirty-one billion, two hundred twenty-one million, three hundred ten thousand, two hundred twenty-one".