1321201021321 has 16 divisors (see below), whose sum is σ = 1449931285440. Its totient is φ = 1199488530240.

The previous prime is 1321201021297. The next prime is 1321201021337. The reversal of 1321201021321 is 1231201021231.

It is a cyclic number.

It is not a de Polignac number, because 1321201021321 - 2²¹ = 1321198924169 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1321201021351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15212710 + ... + 15299311.

It is an arithmetic number, because the mean of its divisors is an integer number (90620705340).

Almost surely, 2^{1321201021321} is an apocalyptic number.

It is an amenable number.

1321201021321 is a deficient number, since it is larger than the sum of its proper divisors (128730264119).

1321201021321 is a wasteful number, since it uses less digits than its factorization.

1321201021321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30512136.

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

Adding to 1321201021321 its reverse (1231201021231), we get a palindrome (2552402042552).

The spelling of 1321201021321 in words is "one trillion, three hundred twenty-one billion, two hundred one million, twenty-one thousand, three hundred twenty-one".