12307221 has 12 divisors (see below), whose sum is σ = 18435872. Its totient is φ = 8204652.

The previous prime is 12307213. The next prime is 12307237. The reversal of 12307221 is 12270321.

It is not a de Polignac number, because 12307221 - 2³ = 12307213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12307194 and 12307203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12307261) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 25081 + ... + 25566.

Almost surely, 2^12307221 is an apocalyptic number.

It is an amenable number.

12307221 is a deficient number, since it is larger than the sum of its proper divisors (6128651).

12307221 is an frugal number, since it uses more digits than its factorization.

12307221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50662 (or 50650 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 18.

The square root of 12307221 is about 3508.1649049040. The cubic root of 12307221 is about 230.8801874882.

Adding to 12307221 its reverse (12270321), we get a palindrome (24577542).

The spelling of 12307221 in words is "twelve million, three hundred seven thousand, two hundred twenty-one".