1311331320 has 96 divisors (see below), whose sum is σ = 4589676000. Its totient is φ = 322788096.

The previous prime is 1311331297. The next prime is 1311331321. The reversal of 1311331320 is 231331131.

It is a happy number.

1311331320 is a `hidden beast` number, since 1 + 3 + 11 + 331 + 320 = 666.

1311331320 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 1311331293 and 1311331302.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1311331321) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 135420 + ... + 144779.

It is an arithmetic number, because the mean of its divisors is an integer number (47809125).

Almost surely, 2^1311331320 is an apocalyptic number.

1311331320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1311331320 is an abundant number, since it is smaller than the sum of its proper divisors (3278344680).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1311331320 is a wasteful number, since it uses less digits than its factorization.

1311331320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 280229 (or 280222 counting only the distinct ones).

The product of its (nonzero) digits is 162, while the sum is 18.

The square root of 1311331320 is about 36212.3089570384. The cubic root of 1311331320 is about 1094.5547198089.

Adding to 1311331320 its reverse (231331131), we get a palindrome (1542662451).

The spelling of 1311331320 in words is "one billion, three hundred eleven million, three hundred thirty-one thousand, three hundred twenty".