2105544051521 has 2 divisors, whose sum is σ = 2105544051522. Its totient is φ = 2105544051520.

The previous prime is 2105544051493. The next prime is 2105544051551. The reversal of 2105544051521 is 1251504455012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2099134447921 + 6409603600 = 1448839^2 + 80060^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2105544051521 is a prime.

It is not a weakly prime, because it can be changed into another prime (2105544051551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1052772025760 + 1052772025761.

It is an arithmetic number, because the mean of its divisors is an integer number (1052772025761).

Almost surely, 2^{2105544051521} is an apocalyptic number.

It is an amenable number.

2105544051521 is a deficient number, since it is larger than the sum of its proper divisors (1).

2105544051521 is an equidigital number, since it uses as much as digits as its factorization.

2105544051521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40000, while the sum is 35.

The spelling of 2105544051521 in words is "two trillion, one hundred five billion, five hundred forty-four million, fifty-one thousand, five hundred twenty-one".