1311601321 has 4 divisors (see below), whose sum is σ = 1333103044. Its totient is φ = 1290099600.

The previous prime is 1311601307. The next prime is 1311601337. The reversal of 1311601321 is 1231061131.

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 95335696 + 1216265625 = 9764^2 + 34875^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1311601321 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1311601301) 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, 10750770 + ... + 10750891.

It is an arithmetic number, because the mean of its divisors is an integer number (333275761).

Almost surely, 2^1311601321 is an apocalyptic number.

It is an amenable number.

1311601321 is a deficient number, since it is larger than the sum of its proper divisors (21501723).

1311601321 is an equidigital number, since it uses as much as digits as its factorization.

1311601321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21501722.

The product of its (nonzero) digits is 108, while the sum is 19.

The square root of 1311601321 is about 36216.0367931114. The cubic root of 1311601321 is about 1094.6298370031.

Adding to 1311601321 its reverse (1231061131), we get a palindrome (2542662452).

The spelling of 1311601321 in words is "one billion, three hundred eleven million, six hundred one thousand, three hundred twenty-one".