1331320231205 has 4 divisors (see below), whose sum is σ = 1597584277452. Its totient is φ = 1065056184960.

The previous prime is 1331320231201. The next prime is 1331320231211. The reversal of 1331320231205 is 5021320231331.

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 463682007364 + 867638223841 = 680942^2 + 931471^2 .

It is not a de Polignac number, because 1331320231205 - 2² = 1331320231201 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 (1331320231201) 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 3 ways as a sum of consecutive naturals, for example, 133132023116 + ... + 133132023125.

It is an arithmetic number, because the mean of its divisors is an integer number (399396069363).

Almost surely, 2^{1331320231205} is an apocalyptic number.

It is an amenable number.

1331320231205 is a deficient number, since it is larger than the sum of its proper divisors (266264046247).

1331320231205 is an equidigital number, since it uses as much as digits as its factorization.

1331320231205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 266264046246.

The product of its (nonzero) digits is 3240, while the sum is 26.

Adding to 1331320231205 its reverse (5021320231331), we get a palindrome (6352640462536).

The spelling of 1331320231205 in words is "one trillion, three hundred thirty-one billion, three hundred twenty million, two hundred thirty-one thousand, two hundred five".