12220021 has 16 divisors (see below), whose sum is σ = 14284800. Its totient is φ = 10335600.

The previous prime is 12220003. The next prime is 12220031. The reversal of 12220021 is 12002221.

It is not a de Polignac number, because 12220021 - 2¹⁷ = 12088949 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12220031) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11836 + ... + 12826.

It is an arithmetic number, because the mean of its divisors is an integer number (892800).

Almost surely, 2^12220021 is an apocalyptic number.

12220021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12220021 is a deficient number, since it is larger than the sum of its proper divisors (2064779).

12220021 is a wasteful number, since it uses less digits than its factorization.

12220021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1080.

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 12220021 is about 3495.7146622686. The cubic root of 12220021 is about 230.3336116454. Note that the first 3 decimals are identical.

Adding to 12220021 its reverse (12002221), we get a palindrome (24222242).

It can be divided in two parts, 122200 and 21, that added together give a palindrome (122221).

The spelling of 12220021 in words is "twelve million, two hundred twenty thousand, twenty-one".