2100212101081 has 2 divisors, whose sum is σ = 2100212101082. Its totient is φ = 2100212101080.

The previous prime is 2100212101073. The next prime is 2100212101093. The reversal of 2100212101081 is 1801012120012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1556777748681 + 543434352400 = 1247709^2 + 737180^2 .

It is a cyclic number.

It is not a de Polignac number, because 2100212101081 - 2³ = 2100212101073 is a prime.

It is a super-2 number, since 2×2100212101081² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2100212101051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1050106050540 + 1050106050541.

It is an arithmetic number, because the mean of its divisors is an integer number (1050106050541).

Almost surely, 2^{2100212101081} is an apocalyptic number.

It is an amenable number.

2100212101081 is a deficient number, since it is larger than the sum of its proper divisors (1).

2100212101081 is an equidigital number, since it uses as much as digits as its factorization.

2100212101081 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 2100212101081 its reverse (1801012120012), we get a palindrome (3901224221093).

The spelling of 2100212101081 in words is "two trillion, one hundred billion, two hundred twelve million, one hundred one thousand, eighty-one".