20213324320081 has 2 divisors, whose sum is σ = 20213324320082. Its totient is φ = 20213324320080.

The previous prime is 20213324320009. The next prime is 20213324320177. The reversal of 20213324320081 is 18002342331202.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20126358310081 + 86966010000 = 4486241^2 + 294900^2 .

It is a cyclic number.

It is not a de Polignac number, because 20213324320081 - 2⁷ = 20213324319953 is a prime.

It is a super-2 number, since 2×20213324320081² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20213324321081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10106662160040 + 10106662160041.

It is an arithmetic number, because the mean of its divisors is an integer number (10106662160041).

Almost surely, 2^{20213324320081} is an apocalyptic number.

It is an amenable number.

20213324320081 is a deficient number, since it is larger than the sum of its proper divisors (1).

20213324320081 is an equidigital number, since it uses as much as digits as its factorization.

20213324320081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13824, while the sum is 31.

Adding to 20213324320081 its reverse (18002342331202), we get a palindrome (38215666651283).

The spelling of 20213324320081 in words is "twenty trillion, two hundred thirteen billion, three hundred twenty-four million, three hundred twenty thousand, eighty-one".