21413300221 has 4 divisors (see below), whose sum is σ = 21419392252. Its totient is φ = 21407208192.

The previous prime is 21413300197. The next prime is 21413300239. The reversal of 21413300221 is 12200331412.

It is a happy number.

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 19877052196 + 1536248025 = 140986^2 + 39195^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21413300221 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 (21413300291) 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, 3040740 + ... + 3047773.

It is an arithmetic number, because the mean of its divisors is an integer number (5354848063).

Almost surely, 2^21413300221 is an apocalyptic number.

It is an amenable number.

21413300221 is a deficient number, since it is larger than the sum of its proper divisors (6092031).

21413300221 is an equidigital number, since it uses as much as digits as its factorization.

21413300221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6092030.

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

Adding to 21413300221 its reverse (12200331412), we get a palindrome (33613631633).

The spelling of 21413300221 in words is "twenty-one billion, four hundred thirteen million, three hundred thousand, two hundred twenty-one".