12400221 has 8 divisors (see below), whose sum is σ = 16766784. Its totient is φ = 8150240.

The previous prime is 12400183. The next prime is 12400231. The reversal of 12400221 is 12200421.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12400221 - 2¹⁰ = 12399197 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12400197 and 12400206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12400231) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28896 + ... + 29321.

It is an arithmetic number, because the mean of its divisors is an integer number (2095848).

Almost surely, 2^12400221 is an apocalyptic number.

It is an amenable number.

12400221 is a deficient number, since it is larger than the sum of its proper divisors (4366563).

12400221 is an equidigital number, since it uses as much as digits as its factorization.

12400221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58291.

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 12400221 is about 3521.3947520833. The cubic root of 12400221 is about 231.4602805094.

Adding to 12400221 its reverse (12200421), we get a palindrome (24600642).

It can be divided in two parts, 12400 and 221, that added together give a palindrome (12621).

The spelling of 12400221 in words is "twelve million, four hundred thousand, two hundred twenty-one".