21220010011181 has 2 divisors, whose sum is σ = 21220010011182. Its totient is φ = 21220010011180.

The previous prime is 21220010011141. The next prime is 21220010011247. The reversal of 21220010011181 is 18111001002212.

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., 21118482385225 + 101527625956 = 4595485^2 + 318634^2 .

It is a cyclic number.

It is not a de Polignac number, because 21220010011181 - 2³⁰ = 21218936269357 is a prime.

It is a super-2 number, since 2×21220010011181² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21220010011141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610005005590 + 10610005005591.

It is an arithmetic number, because the mean of its divisors is an integer number (10610005005591).

Almost surely, 2^{21220010011181} is an apocalyptic number.

It is an amenable number.

21220010011181 is a deficient number, since it is larger than the sum of its proper divisors (1).

21220010011181 is an equidigital number, since it uses as much as digits as its factorization.

21220010011181 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 64, while the sum is 20.

Adding to 21220010011181 its reverse (18111001002212), we get a palindrome (39331011013393).

The spelling of 21220010011181 in words is "twenty-one trillion, two hundred twenty billion, ten million, eleven thousand, one hundred eighty-one".