12217845 has 16 divisors (see below), whose sum is σ = 20223360. Its totient is φ = 6291264.

The previous prime is 12217811. The next prime is 12217859. The reversal of 12217845 is 54871221.

It is not a de Polignac number, because 12217845 - 2⁷ = 12217717 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13609 + ... + 14478.

It is an arithmetic number, because the mean of its divisors is an integer number (1263960).

Almost surely, 2^12217845 is an apocalyptic number.

12217845 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

12217845 is a deficient number, since it is larger than the sum of its proper divisors (8005515).

12217845 is a wasteful number, since it uses less digits than its factorization.

12217845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28124.

The product of its digits is 4480, while the sum is 30.

The square root of 12217845 is about 3495.4034101946. The cubic root of 12217845 is about 230.3199391187.

The spelling of 12217845 in words is "twelve million, two hundred seventeen thousand, eight hundred forty-five".