19662865724089 has 9 divisors (see below), whose sum is σ = 22873165623567. Its totient is φ = 16853858300664.

The previous prime is 19662865724057. The next prime is 19662865724093. The reversal of 19662865724089 is 98042756826691.

The square root of 19662865724089 is 4434283.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 19483987480489 + 178878243600 = 4414067^2 + 422940^2 .

It is not a de Polignac number, because 19662865724089 - 2⁵ = 19662865724057 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19662865724009) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 30723247 + ... + 31356715.

It is an arithmetic number, because the mean of its divisors is an integer number (2541462847063).

Almost surely, 2^{19662865724089} is an apocalyptic number.

19662865724089 is the 4434283-rd square number.

19662865724089 is the 2217142-nd centered octagonal number.

It is an amenable number.

19662865724089 is a deficient number, since it is larger than the sum of its proper divisors (3210299899478).

19662865724089 is an frugal number, since it uses more digits than its factorization.

19662865724089 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1266952 (or 633476 counting only the distinct ones).

The product of its (nonzero) digits is 627056640, while the sum is 73.

The spelling of 19662865724089 in words is "nineteen trillion, six hundred sixty-two billion, eight hundred sixty-five million, seven hundred twenty-four thousand, eighty-nine".