21201222113 has 4 divisors (see below), whose sum is σ = 21456658608. Its totient is φ = 20945785620.

The previous prime is 21201222101. The next prime is 21201222193. The reversal of 21201222113 is 31122210212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21201222113 - 2¹⁰ = 21201221089 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21201222091 and 21201222100.

It is not an unprimeable number, because it can be changed into a prime (21201222193) 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, 127718123 + ... + 127718288.

It is an arithmetic number, because the mean of its divisors is an integer number (5364164652).

Almost surely, 2^21201222113 is an apocalyptic number.

It is an amenable number.

21201222113 is a deficient number, since it is larger than the sum of its proper divisors (255436495).

21201222113 is an equidigital number, since it uses as much as digits as its factorization.

21201222113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255436494.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 21201222113 its reverse (31122210212), we get a palindrome (52323432325).

The spelling of 21201222113 in words is "twenty-one billion, two hundred one million, two hundred twenty-two thousand, one hundred thirteen".