20320321181 has 2 divisors, whose sum is σ = 20320321182. Its totient is φ = 20320321180.

The previous prime is 20320321171. The next prime is 20320321213. The reversal of 20320321181 is 18112302302.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19748680900 + 571640281 = 140530^2 + 23909^2 .

It is a cyclic number.

It is not a de Polignac number, because 20320321181 - 2¹⁰ = 20320320157 is a prime.

It is a super-3 number, since 3×20320321181³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20320321121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10160160590 + 10160160591.

It is an arithmetic number, because the mean of its divisors is an integer number (10160160591).

Almost surely, 2^20320321181 is an apocalyptic number.

It is an amenable number.

20320321181 is a deficient number, since it is larger than the sum of its proper divisors (1).

20320321181 is an equidigital number, since it uses as much as digits as its factorization.

20320321181 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 576, while the sum is 23.

Adding to 20320321181 its reverse (18112302302), we get a palindrome (38432623483).

The spelling of 20320321181 in words is "twenty billion, three hundred twenty million, three hundred twenty-one thousand, one hundred eighty-one".