1321131020221 has 16 divisors (see below), whose sum is σ = 1351290859776. Its totient is φ = 1291057767936.

The previous prime is 1321131020213. The next prime is 1321131020239. The reversal of 1321131020221 is 1220201311231.

It is a cyclic number.

It is not a de Polignac number, because 1321131020221 - 2³ = 1321131020213 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 (1321131020201) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 200868085 + ... + 200874661.

It is an arithmetic number, because the mean of its divisors is an integer number (84455678736).

Almost surely, 2^{1321131020221} is an apocalyptic number.

It is an amenable number.

1321131020221 is a deficient number, since it is larger than the sum of its proper divisors (30159839555).

1321131020221 is an equidigital number, since it uses as much as digits as its factorization.

1321131020221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12468.

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

Adding to 1321131020221 its reverse (1220201311231), we get a palindrome (2541332331452).

The spelling of 1321131020221 in words is "one trillion, three hundred twenty-one billion, one hundred thirty-one million, twenty thousand, two hundred twenty-one".