12971531 has 4 divisors (see below), whose sum is σ = 13100064. Its totient is φ = 12843000.

The previous prime is 12971521. The next prime is 12971533. The reversal of 12971531 is 13517921.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13517921 = 73 ⋅185177.

It is a cyclic number.

It is not a de Polignac number, because 12971531 - 2¹⁴ = 12955147 is a prime.

It is a super-3 number, since 3×12971531³ (a number of 22 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12971494 and 12971503.

It is not an unprimeable number, because it can be changed into a prime (12971533) 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 3 ways as a sum of consecutive naturals, for example, 64115 + ... + 64316.

It is an arithmetic number, because the mean of its divisors is an integer number (3275016).

Almost surely, 2^12971531 is an apocalyptic number.

12971531 is a deficient number, since it is larger than the sum of its proper divisors (128533).

12971531 is a wasteful number, since it uses less digits than its factorization.

12971531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128532.

The product of its digits is 1890, while the sum is 29.

The square root of 12971531 is about 3601.6011717013. The cubic root of 12971531 is about 234.9617019225.

The spelling of 12971531 in words is "twelve million, nine hundred seventy-one thousand, five hundred thirty-one".