12156971 has 4 divisors (see below), whose sum is σ = 12173472. Its totient is φ = 12140472.

The previous prime is 12156899. The next prime is 12156983. The reversal of 12156971 is 17965121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17965121 = 547 ⋅32843.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12156971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12156671) 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, 7091 + ... + 8636.

It is an arithmetic number, because the mean of its divisors is an integer number (3043368).

Almost surely, 2^12156971 is an apocalyptic number.

12156971 is a deficient number, since it is larger than the sum of its proper divisors (16501).

12156971 is an equidigital number, since it uses as much as digits as its factorization.

12156971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16500.

The product of its digits is 3780, while the sum is 32.

The square root of 12156971 is about 3486.6848151217. The cubic root of 12156971 is about 229.9367879217.

The spelling of 12156971 in words is "twelve million, one hundred fifty-six thousand, nine hundred seventy-one".