21000211303081 has 2 divisors, whose sum is σ = 21000211303082. Its totient is φ = 21000211303080.

The previous prime is 21000211303013. The next prime is 21000211303153. The reversal of 21000211303081 is 18030311200012.

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., 16523533957225 + 4476677345856 = 4064915^2 + 2115816^2 .

It is a cyclic number.

It is not a de Polignac number, because 21000211303081 - 2¹⁹ = 21000210778793 is a prime.

It is a super-2 number, since 2×21000211303081² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21000211903081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500105651540 + 10500105651541.

It is an arithmetic number, because the mean of its divisors is an integer number (10500105651541).

Almost surely, 2^{21000211303081} is an apocalyptic number.

It is an amenable number.

21000211303081 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000211303081 is an equidigital number, since it uses as much as digits as its factorization.

21000211303081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 22.

Adding to 21000211303081 its reverse (18030311200012), we get a palindrome (39030522503093).

The spelling of 21000211303081 in words is "twenty-one trillion, two hundred eleven million, three hundred three thousand, eighty-one".