13123531 has 2 divisors, whose sum is σ = 13123532. Its totient is φ = 13123530.

The previous prime is 13123529. The next prime is 13123577. The reversal of 13123531 is 13532131.

It is a weak prime.

It is an emirp because it is prime and its reverse (13532131) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13123531 - 2¹ = 13123529 is a prime.

It is a super-2 number, since 2×13123531² = 344454131815922, which contains 22 as substring.

Together with 13123529, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 13123499 and 13123508.

It is not a weakly prime, because it can be changed into another prime (13123931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6561765 + 6561766.

It is an arithmetic number, because the mean of its divisors is an integer number (6561766).

Almost surely, 2^13123531 is an apocalyptic number.

13123531 is a deficient number, since it is larger than the sum of its proper divisors (1).

13123531 is an equidigital number, since it uses as much as digits as its factorization.

13123531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 270, while the sum is 19.

The square root of 13123531 is about 3622.6414396128. The cubic root of 13123531 is about 235.8758983161.

Adding to 13123531 its reverse (13532131), we get a palindrome (26655662).

The spelling of 13123531 in words is "thirteen million, one hundred twenty-three thousand, five hundred thirty-one".