13111520 has 72 divisors (see below), whose sum is σ = 32836104. Its totient is φ = 4946688.

The previous prime is 13111519. The next prime is 13111561. The reversal of 13111520 is 2511131.

It is a junction number, because it is equal to n+sod(n) for n = 13111495 and 13111504.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 57647 + ... + 57873.

It is an arithmetic number, because the mean of its divisors is an integer number (456057).

Almost surely, 2^13111520 is an apocalyptic number.

13111520 is a gapful number since it is divisible by the number (10) 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 13111520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16418052).

13111520 is an abundant number, since it is smaller than the sum of its proper divisors (19724584).

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

13111520 is a wasteful number, since it uses less digits than its factorization.

13111520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 280 (or 253 counting only the distinct ones).

The product of its (nonzero) digits is 30, while the sum is 14.

The square root of 13111520 is about 3620.9832918698. The cubic root of 13111520 is about 235.8039164142.

Adding to 13111520 its reverse (2511131), we get a palindrome (15622651).

It can be divided in two parts, 13111 and 520, that added together give a palindrome (13631).

The spelling of 13111520 in words is "thirteen million, one hundred eleven thousand, five hundred twenty".