21102201181 has 2 divisors, whose sum is σ = 21102201182. Its totient is φ = 21102201180.

The previous prime is 21102201179. The next prime is 21102201187. The reversal of 21102201181 is 18110220112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19462761081 + 1639440100 = 139509^2 + 40490^2 .

It is a cyclic number.

It is not a de Polignac number, because 21102201181 - 2¹ = 21102201179 is a prime.

It is a super-2 number, since 2×21102201181² (a number of 21 digits) contains 22 as substring.

Together with 21102201179, 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 (21102201187) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10551100590 + 10551100591.

It is an arithmetic number, because the mean of its divisors is an integer number (10551100591).

Almost surely, 2^21102201181 is an apocalyptic number.

It is an amenable number.

21102201181 is a deficient number, since it is larger than the sum of its proper divisors (1).

21102201181 is an equidigital number, since it uses as much as digits as its factorization.

21102201181 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 19.

Adding to 21102201181 its reverse (18110220112), we get a palindrome (39212421293).

The spelling of 21102201181 in words is "twenty-one billion, one hundred two million, two hundred one thousand, one hundred eighty-one".