12205811 has 4 divisors (see below), whose sum is σ = 12319992. Its totient is φ = 12091632.

The previous prime is 12205799. The next prime is 12205829. The reversal of 12205811 is 11850221.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 11850221 = 23 ⋅515227.

It is a cyclic number.

It is not a de Polignac number, because 12205811 - 2⁶ = 12205747 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12205891) 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, 56930 + ... + 57143.

It is an arithmetic number, because the mean of its divisors is an integer number (3079998).

Almost surely, 2^12205811 is an apocalyptic number.

12205811 is a deficient number, since it is larger than the sum of its proper divisors (114181).

12205811 is a wasteful number, since it uses less digits than its factorization.

12205811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114180.

The product of its (nonzero) digits is 160, while the sum is 20.

The square root of 12205811 is about 3493.6815825144. The cubic root of 12205811 is about 230.2442961927.

The spelling of 12205811 in words is "twelve million, two hundred five thousand, eight hundred eleven".