12180815 has 4 divisors (see below), whose sum is σ = 14616984. Its totient is φ = 9744648.

The previous prime is 12180803. The next prime is 12180821. The reversal of 12180815 is 51808121.

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 12180815 - 2¹⁸ = 11918671 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1218077 + ... + 1218086.

It is an arithmetic number, because the mean of its divisors is an integer number (3654246).

Almost surely, 2^12180815 is an apocalyptic number.

12180815 is a deficient number, since it is larger than the sum of its proper divisors (2436169).

12180815 is an equidigital number, since it uses as much as digits as its factorization.

12180815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2436168.

The product of its (nonzero) digits is 640, while the sum is 26.

The square root of 12180815 is about 3490.1024340268. The cubic root of 12180815 is about 230.0870181131.

Adding to 12180815 its reverse (51808121), we get a palindrome (63988936).

The spelling of 12180815 in words is "twelve million, one hundred eighty thousand, eight hundred fifteen".