21201022201181 has 2 divisors, whose sum is σ = 21201022201182. Its totient is φ = 21201022201180.

The previous prime is 21201022201129. The next prime is 21201022201199. The reversal of 21201022201181 is 18110222010212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21063822337156 + 137199864025 = 4589534^2 + 370405^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21201022201181 is a prime.

It is a super-2 number, since 2×21201022201181² (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 (21201022251181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600511100590 + 10600511100591.

It is an arithmetic number, because the mean of its divisors is an integer number (10600511100591).

Almost surely, 2^{21201022201181} is an apocalyptic number.

It is an amenable number.

21201022201181 is a deficient number, since it is larger than the sum of its proper divisors (1).

21201022201181 is an equidigital number, since it uses as much as digits as its factorization.

21201022201181 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 256, while the sum is 23.

Adding to 21201022201181 its reverse (18110222010212), we get a palindrome (39311244211393).

The spelling of 21201022201181 in words is "twenty-one trillion, two hundred one billion, twenty-two million, two hundred one thousand, one hundred eighty-one".