21342210221 has 8 divisors (see below), whose sum is σ = 21655556280. Its totient is φ = 21031048192.

The previous prime is 21342210203. The next prime is 21342210251. The reversal of 21342210221 is 12201224312.

It can be written as a sum of positive squares in 4 ways, for example, as 4200854596 + 17141355625 = 64814^2 + 130925^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21342210221 - 2⁶ = 21342210157 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21342210193 and 21342210202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21342210251) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 526316 + ... + 565413.

It is an arithmetic number, because the mean of its divisors is an integer number (2706944535).

Almost surely, 2^21342210221 is an apocalyptic number.

It is an amenable number.

21342210221 is a deficient number, since it is larger than the sum of its proper divisors (313346059).

21342210221 is a wasteful number, since it uses less digits than its factorization.

21342210221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1092015.

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21342210221 its reverse (12201224312), we get a palindrome (33543434533).

The spelling of 21342210221 in words is "twenty-one billion, three hundred forty-two million, two hundred ten thousand, two hundred twenty-one".