13381531 has 4 divisors (see below), whose sum is σ = 13743232. Its totient is φ = 13019832.

The previous prime is 13381523. The next prime is 13381549. The reversal of 13381531 is 13518331.

13381531 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13518331 = 1097 ⋅12323.

It is a cyclic number.

It is not a de Polignac number, because 13381531 - 2³ = 13381523 is a prime.

It is a super-2 number, since 2×13381531² = 358130743807922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 13381496 and 13381505.

It is not an unprimeable number, because it can be changed into a prime (13381231) 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, 180795 + ... + 180868.

It is an arithmetic number, because the mean of its divisors is an integer number (3435808).

Almost surely, 2^13381531 is an apocalyptic number.

13381531 is a deficient number, since it is larger than the sum of its proper divisors (361701).

13381531 is an equidigital number, since it uses as much as digits as its factorization.

13381531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 361700.

The product of its digits is 1080, while the sum is 25.

The square root of 13381531 is about 3658.0775005459. The cubic root of 13381531 is about 237.4115999723.

Adding to 13381531 its reverse (13518331), we get a palindrome (26899862).

The spelling of 13381531 in words is "thirteen million, three hundred eighty-one thousand, five hundred thirty-one".