13115538 has 48 divisors (see below), whose sum is σ = 29877120. Its totient is φ = 4153248.

The previous prime is 13115537. The next prime is 13115563. The reversal of 13115538 is 83551131.

13115538 is a `hidden beast` number, since 13 + 115 + 538 = 666.

It is not an unprimeable number, because it can be changed into a prime (13115533) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 31093 + ... + 31511.

It is an arithmetic number, because the mean of its divisors is an integer number (622440).

Almost surely, 2^13115538 is an apocalyptic number.

13115538 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 13115538, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14938560).

13115538 is an abundant number, since it is smaller than the sum of its proper divisors (16761582).

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

13115538 is a wasteful number, since it uses less digits than its factorization.

13115538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 511 (or 508 counting only the distinct ones).

The product of its digits is 1800, while the sum is 27.

The square root of 13115538 is about 3621.5380710411. The cubic root of 13115538 is about 235.8280011724.

Adding to 13115538 its reverse (83551131), we get a palindrome (96666669).

The spelling of 13115538 in words is "thirteen million, one hundred fifteen thousand, five hundred thirty-eight".