21201444001181 has 2 divisors, whose sum is σ = 21201444001182. Its totient is φ = 21201444001180.

The previous prime is 21201444001123. The next prime is 21201444001183. The reversal of 21201444001181 is 18110044410212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19560354898681 + 1641089102500 = 4422709^2 + 1281050^2 .

It is a cyclic number.

It is not a de Polignac number, because 21201444001181 - 2¹⁴ = 21201443984797 is a prime.

It is a super-5 number, since 5×21201444001181⁵ (a number of 68 digits) contains 55555 as substring. Note that it is a super-d number also for d = 2.

Together with 21201444001183, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21201444001183) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600722000590 + 10600722000591.

It is an arithmetic number, because the mean of its divisors is an integer number (10600722000591).

Almost surely, 2^{21201444001181} is an apocalyptic number.

It is an amenable number.

21201444001181 is a deficient number, since it is larger than the sum of its proper divisors (1).

21201444001181 is an equidigital number, since it uses as much as digits as its factorization.

21201444001181 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2048, while the sum is 29.

Adding to 21201444001181 its reverse (18110044410212), we get a palindrome (39311488411393).

The spelling of 21201444001181 in words is "twenty-one trillion, two hundred one billion, four hundred forty-four million, one thousand, one hundred eighty-one".