21231332113 has 6 divisors (see below), whose sum is σ = 22553699126. Its totient is φ = 19982429952.

The previous prime is 21231332093. The next prime is 21231332153. The reversal of 21231332113 is 31123313212.

It can be written as a sum of positive squares in 3 ways, for example, as 10976124289 + 10255207824 = 104767^2 + 101268^2 .

It is a de Polignac number, because none of the positive numbers 2^k-21231332113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21231332153) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 36732120 + ... + 36732697.

Almost surely, 2^21231332113 is an apocalyptic number.

It is an amenable number.

21231332113 is a deficient number, since it is larger than the sum of its proper divisors (1322367013).

21231332113 is an equidigital number, since it uses as much as digits as its factorization.

21231332113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73464851 (or 73464834 counting only the distinct ones).

The product of its digits is 648, while the sum is 22.

Adding to 21231332113 its reverse (31123313212), we get a palindrome (52354645325).

The spelling of 21231332113 in words is "twenty-one billion, two hundred thirty-one million, three hundred thirty-two thousand, one hundred thirteen".