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12531 = 34177
BaseRepresentation
bin11000011110011
3122012010
43003303
5400111
6134003
751351
oct30363
918163
1012531
119462
127303
13591c
1447d1
153aa6
hex30f3

12531 has 4 divisors (see below), whose sum is σ = 16712. Its totient is φ = 8352.

The previous prime is 12527. The next prime is 12539. The reversal of 12531 is 13521.

12531 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: 13521 = 34507.

It is not a de Polignac number, because 12531 - 22 = 12527 is a prime.

It is a super-2 number, since 2×125312 = 314051922, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

It is a zygodrome in base 2.

It is not an unprimeable number, because it can be changed into a prime (12539) 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, 2086 + ... + 2091.

It is an arithmetic number, because the mean of its divisors is an integer number (4178).

212531 is an apocalyptic number.

12531 is a deficient number, since it is larger than the sum of its proper divisors (4181).

12531 is an equidigital number, since it uses as much as digits as its factorization.

12531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4180.

The product of its digits is 30, while the sum is 12.

The square root of 12531 is about 111.9419492416. The cubic root of 12531 is about 23.2271135639.

Adding to 12531 its product of digits (30), we get a triangular number (12561 = T158).

Subtracting 12531 from its reverse (13521), we obtain a triangular number (990 = T44).

The spelling of 12531 in words is "twelve thousand, five hundred thirty-one".

Divisors: 1 3 4177 12531