12205021021 has 16 divisors (see below), whose sum is σ = 13278311424. Its totient is φ = 11171499264.

The previous prime is 12205020983. The next prime is 12205021033. The reversal of 12205021021 is 12012050221.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 12205021021 - 2¹³ = 12205012829 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12205020986 and 12205021004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12205021061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2427316 + ... + 2432338.

It is an arithmetic number, because the mean of its divisors is an integer number (829894464).

Almost surely, 2^12205021021 is an apocalyptic number.

It is an amenable number.

12205021021 is a deficient number, since it is larger than the sum of its proper divisors (1073290403).

12205021021 is a wasteful number, since it uses less digits than its factorization.

12205021021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8940.

The product of its (nonzero) digits is 80, while the sum is 16.

Adding to 12205021021 its reverse (12012050221), we get a palindrome (24217071242).

The spelling of 12205021021 in words is "twelve billion, two hundred five million, twenty-one thousand, twenty-one".