1311531138816 has 144 divisors (see below), whose sum is σ = 3651732564480. Its totient is φ = 417092177920.

The previous prime is 1311531138763. The next prime is 1311531138817. The reversal of 1311531138816 is 6188311351131.

It is a super-2 number, since 2×1311531138816² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1311531138817) 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, 6775861 + ... + 6966731.

It is an arithmetic number, because the mean of its divisors is an integer number (25359253920).

Almost surely, 2^{1311531138816} is an apocalyptic number.

1311531138816 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1311531138816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1825866282240).

1311531138816 is an abundant number, since it is smaller than the sum of its proper divisors (2340201425664).

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

1311531138816 is a wasteful number, since it uses less digits than its factorization.

1311531138816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191302 (or 191288 counting only the distinct ones).

The product of its digits is 51840, while the sum is 42.

Adding to 1311531138816 its reverse (6188311351131), we get a palindrome (7499842489947).

The spelling of 1311531138816 in words is "one trillion, three hundred eleven billion, five hundred thirty-one million, one hundred thirty-eight thousand, eight hundred sixteen".