21102011001061 has 2 divisors, whose sum is σ = 21102011001062. Its totient is φ = 21102011001060.

The previous prime is 21102011001047. The next prime is 21102011001151. The reversal of 21102011001061 is 16010011020112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19648997732961 + 1453013268100 = 4432719^2 + 1205410^2 .

It is a cyclic number.

It is not a de Polignac number, because 21102011001061 - 2¹⁵ = 21102010968293 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21102011601061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10551005500530 + 10551005500531.

It is an arithmetic number, because the mean of its divisors is an integer number (10551005500531).

Almost surely, 2^{21102011001061} is an apocalyptic number.

It is an amenable number.

21102011001061 is a deficient number, since it is larger than the sum of its proper divisors (1).

21102011001061 is an equidigital number, since it uses as much as digits as its factorization.

21102011001061 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24, while the sum is 16.

Adding to 21102011001061 its reverse (16010011020112), we get a palindrome (37112022021173).

The spelling of 21102011001061 in words is "twenty-one trillion, one hundred two billion, eleven million, one thousand, sixty-one".