12171559 has 4 divisors (see below), whose sum is σ = 12191904. Its totient is φ = 12151216.

The previous prime is 12171539. The next prime is 12171581. The reversal of 12171559 is 95517121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 12171559 - 2⁵ = 12171527 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12171559.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12171529) 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, 9247 + ... + 10480.

It is an arithmetic number, because the mean of its divisors is an integer number (3047976).

Almost surely, 2^12171559 is an apocalyptic number.

12171559 is a deficient number, since it is larger than the sum of its proper divisors (20345).

12171559 is an equidigital number, since it uses as much as digits as its factorization.

12171559 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20344.

The product of its digits is 3150, while the sum is 31.

The square root of 12171559 is about 3488.7761464445. The cubic root of 12171559 is about 230.0287235709.

The spelling of 12171559 in words is "twelve million, one hundred seventy-one thousand, five hundred fifty-nine".