21108723551753 has 2 divisors, whose sum is σ = 21108723551754. Its totient is φ = 21108723551752.

The previous prime is 21108723551719. The next prime is 21108723551771. The reversal of 21108723551753 is 35715532780112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21104073402889 + 4650148864 = 4593917^2 + 68192^2 .

It is a cyclic number.

It is not a de Polignac number, because 21108723551753 - 2¹⁰ = 21108723550729 is a prime.

It is not a weakly prime, because it can be changed into another prime (21108723551453) 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, 10554361775876 + 10554361775877.

It is an arithmetic number, because the mean of its divisors is an integer number (10554361775877).

Almost surely, 2^{21108723551753} is an apocalyptic number.

It is an amenable number.

21108723551753 is a deficient number, since it is larger than the sum of its proper divisors (1).

21108723551753 is an equidigital number, since it uses as much as digits as its factorization.

21108723551753 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1764000, while the sum is 50.

The spelling of 21108723551753 in words is "twenty-one trillion, one hundred eight billion, seven hundred twenty-three million, five hundred fifty-one thousand, seven hundred fifty-three".