21323331181 has 2 divisors, whose sum is σ = 21323331182. Its totient is φ = 21323331180.

The previous prime is 21323331163. The next prime is 21323331233. The reversal of 21323331181 is 18113332312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20748962025 + 574369156 = 144045^2 + 23966^2 .

It is a cyclic number.

It is not a de Polignac number, because 21323331181 - 2¹⁷ = 21323200109 is a prime.

It is a super-2 number, since 2×21323331181² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21323331131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10661665590 + 10661665591.

It is an arithmetic number, because the mean of its divisors is an integer number (10661665591).

Almost surely, 2^21323331181 is an apocalyptic number.

It is an amenable number.

21323331181 is a deficient number, since it is larger than the sum of its proper divisors (1).

21323331181 is an equidigital number, since it uses as much as digits as its factorization.

21323331181 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2592, while the sum is 28.

Adding to 21323331181 its reverse (18113332312), we get a palindrome (39436663493).

The spelling of 21323331181 in words is "twenty-one billion, three hundred twenty-three million, three hundred thirty-one thousand, one hundred eighty-one".