12211918 has 4 divisors (see below), whose sum is σ = 18317880. Its totient is φ = 6105958.

The previous prime is 12211909. The next prime is 12211937. The reversal of 12211918 is 81911221.

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

It is a junction number, because it is equal to n+sod(n) for n = 12211892 and 12211901.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3052978 + ... + 3052981.

It is an arithmetic number, because the mean of its divisors is an integer number (4579470).

Almost surely, 2^12211918 is an apocalyptic number.

12211918 is a deficient number, since it is larger than the sum of its proper divisors (6105962).

12211918 is an equidigital number, since it uses as much as digits as its factorization.

12211918 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6105961.

The product of its digits is 288, while the sum is 25.

The square root of 12211918 is about 3494.5554795997. Note that the first 3 decimals coincide. The cubic root of 12211918 is about 230.2826895851.

The spelling of 12211918 in words is "twelve million, two hundred eleven thousand, nine hundred eighteen".