19966124161 has 2 divisors, whose sum is σ = 19966124162. Its totient is φ = 19966124160.

The previous prime is 19966124153. The next prime is 19966124209. The reversal of 19966124161 is 16142166991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19727607025 + 238517136 = 140455^2 + 15444^2 .

It is a cyclic number.

It is not a de Polignac number, because 19966124161 - 2³ = 19966124153 is a prime.

It is a super-2 number, since 2×19966124161² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (19966124111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9983062080 + 9983062081.

It is an arithmetic number, because the mean of its divisors is an integer number (9983062081).

Almost surely, 2^19966124161 is an apocalyptic number.

It is an amenable number.

19966124161 is a deficient number, since it is larger than the sum of its proper divisors (1).

19966124161 is an equidigital number, since it uses as much as digits as its factorization.

19966124161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 139968, while the sum is 46.

The spelling of 19966124161 in words is "nineteen billion, nine hundred sixty-six million, one hundred twenty-four thousand, one hundred sixty-one".