221223130021 has 4 divisors (see below), whose sum is σ = 221360622700. Its totient is φ = 221085637344.

The previous prime is 221223130003. The next prime is 221223130033. The reversal of 221223130021 is 120031322122.

221223130021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 194559505921 + 26663624100 = 441089^2 + 163290^2 .

It is a cyclic number.

It is not a de Polignac number, because 221223130021 - 2¹⁷ = 221222998949 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 (221223130061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 68743926 + ... + 68747143.

It is an arithmetic number, because the mean of its divisors is an integer number (55340155675).

Almost surely, 2^221223130021 is an apocalyptic number.

It is an amenable number.

221223130021 is a deficient number, since it is larger than the sum of its proper divisors (137492679).

221223130021 is a wasteful number, since it uses less digits than its factorization.

221223130021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137492678.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 221223130021 its reverse (120031322122), we get a palindrome (341254452143).

The spelling of 221223130021 in words is "two hundred twenty-one billion, two hundred twenty-three million, one hundred thirty thousand, twenty-one".