21663203265101 has 2 divisors, whose sum is σ = 21663203265102. Its totient is φ = 21663203265100.

The previous prime is 21663203265073. The next prime is 21663203265161. The reversal of 21663203265101 is 10156230236612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17586499027876 + 4076704237225 = 4193626^2 + 2019085^2 .

It is a cyclic number.

It is not a de Polignac number, because 21663203265101 - 2¹⁰ = 21663203264077 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21663203265161) 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, 10831601632550 + 10831601632551.

It is an arithmetic number, because the mean of its divisors is an integer number (10831601632551).

Almost surely, 2^{21663203265101} is an apocalyptic number.

It is an amenable number.

21663203265101 is a deficient number, since it is larger than the sum of its proper divisors (1).

21663203265101 is an equidigital number, since it uses as much as digits as its factorization.

21663203265101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 77760, while the sum is 38.

The spelling of 21663203265101 in words is "twenty-one trillion, six hundred sixty-three billion, two hundred three million, two hundred sixty-five thousand, one hundred one".