12531157 has 4 divisors (see below), whose sum is σ = 12540780. Its totient is φ = 12521536.

The previous prime is 12531151. The next prime is 12531163. The reversal of 12531157 is 75113521.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is an interprime number because it is at equal distance from previous prime (12531151) and next prime (12531163).

It can be written as a sum of positive squares in 2 ways, for example, as 427716 + 12103441 = 654^2 + 3479^2 .

It is a cyclic number.

It is not a de Polignac number, because 12531157 - 2³ = 12531149 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12531151) 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, 2482 + ... + 5587.

It is an arithmetic number, because the mean of its divisors is an integer number (3135195).

Almost surely, 2^12531157 is an apocalyptic number.

It is an amenable number.

12531157 is a deficient number, since it is larger than the sum of its proper divisors (9623).

12531157 is an equidigital number, since it uses as much as digits as its factorization.

12531157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9622.

The product of its digits is 1050, while the sum is 25.

The square root of 12531157 is about 3539.9374288255. The cubic root of 12531157 is about 232.2721056714.

Adding to 12531157 its reverse (75113521), we get a palindrome (87644678).

The spelling of 12531157 in words is "twelve million, five hundred thirty-one thousand, one hundred fifty-seven".