11212020181 has 2 divisors, whose sum is σ = 11212020182. Its totient is φ = 11212020180.

The previous prime is 11212020179. The next prime is 11212020191. The reversal of 11212020181 is 18102021211.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10731095281 + 480924900 = 103591^2 + 21930^2 .

It is a cyclic number.

It is not a de Polignac number, because 11212020181 - 2¹ = 11212020179 is a prime.

It is a super-2 number, since 2×11212020181² (a number of 21 digits) contains 22 as substring.

Together with 11212020179, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11212020191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5606010090 + 5606010091.

It is an arithmetic number, because the mean of its divisors is an integer number (5606010091).

Almost surely, 2^11212020181 is an apocalyptic number.

It is an amenable number.

11212020181 is a deficient number, since it is larger than the sum of its proper divisors (1).

11212020181 is an equidigital number, since it uses as much as digits as its factorization.

11212020181 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 11212020181 its reverse (18102021211), we get a palindrome (29314041392).

The spelling of 11212020181 in words is "eleven billion, two hundred twelve million, twenty thousand, one hundred eighty-one".