12221001 has 24 divisors (see below), whose sum is σ = 19306560. Its totient is φ = 7403616.

The previous prime is 12220997. The next prime is 12221021. The reversal of 12221001 is 10012221.

It is not a de Polignac number, because 12221001 - 2² = 12220997 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (12221021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7060 + ... + 8618.

It is an arithmetic number, because the mean of its divisors is an integer number (804440).

Almost surely, 2^12221001 is an apocalyptic number.

It is an amenable number.

12221001 is a deficient number, since it is larger than the sum of its proper divisors (7085559).

12221001 is a wasteful number, since it uses less digits than its factorization.

12221001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1645 (or 1642 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 12221001 is about 3495.8548310821. The cubic root of 12221001 is about 230.3397687790.

Adding to 12221001 its reverse (10012221), we get a palindrome (22233222).

The spelling of 12221001 in words is "twelve million, two hundred twenty-one thousand, one".