20120021022221 has 4 divisors (see below), whose sum is σ = 20120030629500. Its totient is φ = 20120011414944.

The previous prime is 20120021022217. The next prime is 20120021022251. The reversal of 20120021022221 is 12222012002102.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 19445674575625 + 674346446596 = 4409725^2 + 821186^2 .

It is a cyclic number.

It is not a de Polignac number, because 20120021022221 - 2² = 20120021022217 is a prime.

It is a super-2 number, since 2×20120021022221² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20120021022221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20120021022251) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 176666 + ... + 6345963.

It is an arithmetic number, because the mean of its divisors is an integer number (5030007657375).

Almost surely, 2^{20120021022221} is an apocalyptic number.

It is an amenable number.

20120021022221 is a deficient number, since it is larger than the sum of its proper divisors (9607279).

20120021022221 is an equidigital number, since it uses as much as digits as its factorization.

20120021022221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9607278.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 20120021022221 its reverse (12222012002102), we get a palindrome (32342033024323).

The spelling of 20120021022221 in words is "twenty trillion, one hundred twenty billion, twenty-one million, twenty-two thousand, two hundred twenty-one".