12217431 has 4 divisors (see below), whose sum is σ = 16289912. Its totient is φ = 8144952.

The previous prime is 12217427. The next prime is 12217459. The reversal of 12217431 is 13471221.

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

It is not a de Polignac number, because 12217431 - 2² = 12217427 is a prime.

It is a super-2 number, since 2×12217431² = 298531240479522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12217398 and 12217407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12217411) 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, 2036236 + ... + 2036241.

It is an arithmetic number, because the mean of its divisors is an integer number (4072478).

Almost surely, 2^12217431 is an apocalyptic number.

12217431 is a deficient number, since it is larger than the sum of its proper divisors (4072481).

12217431 is an equidigital number, since it uses as much as digits as its factorization.

12217431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4072480.

The product of its digits is 336, while the sum is 21.

The square root of 12217431 is about 3495.3441890606. The cubic root of 12217431 is about 230.3173376361.

Adding to 12217431 its reverse (13471221), we get a palindrome (25688652).

The spelling of 12217431 in words is "twelve million, two hundred seventeen thousand, four hundred thirty-one".