13231557 has 6 divisors (see below), whose sum is σ = 19112262. Its totient is φ = 8821032.

The previous prime is 13231553. The next prime is 13231583. The reversal of 13231557 is 75513231.

It can be written as a sum of positive squares in only one way, i.e., 12916836 + 314721 = 3594^2 + 561^2 .

It is not a de Polignac number, because 13231557 - 2² = 13231553 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 13231557.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13231553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 735078 + ... + 735095.

It is an arithmetic number, because the mean of its divisors is an integer number (3185377).

Almost surely, 2^13231557 is an apocalyptic number.

It is an amenable number.

13231557 is a deficient number, since it is larger than the sum of its proper divisors (5880705).

13231557 is a wasteful number, since it uses less digits than its factorization.

13231557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1470179 (or 1470176 counting only the distinct ones).

The product of its digits is 3150, while the sum is 27.

The square root of 13231557 is about 3637.5207215905. The cubic root of 13231557 is about 236.5213326665.

Adding to 13231557 its reverse (75513231), we get a palindrome (88744788).

The spelling of 13231557 in words is "thirteen million, two hundred thirty-one thousand, five hundred fifty-seven".