21202113113 has 4 divisors (see below), whose sum is σ = 21203013540. Its totient is φ = 21201212688.

The previous prime is 21202113109. The next prime is 21202113131. The reversal of 21202113113 is 31131120212.

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 12984146704 + 8217966409 = 113948^2 + 90653^2 .

It is a cyclic number.

It is not a de Polignac number, because 21202113113 - 2² = 21202113109 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21202113091 and 21202113100.

It is not an unprimeable number, because it can be changed into a prime (21202113103) 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, 413918 + ... + 462311.

It is an arithmetic number, because the mean of its divisors is an integer number (5300753385).

Almost surely, 2^21202113113 is an apocalyptic number.

It is an amenable number.

21202113113 is a deficient number, since it is larger than the sum of its proper divisors (900427).

21202113113 is an equidigital number, since it uses as much as digits as its factorization.

21202113113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 900426.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 21202113113 its reverse (31131120212), we get a palindrome (52333233325).

The spelling of 21202113113 in words is "twenty-one billion, two hundred two million, one hundred thirteen thousand, one hundred thirteen".