19947228277824 has 1323 divisors, whose sum is σ = 66392101834149. Its totient is φ = 5942589649920.

The previous prime is 19947228277817. The next prime is 19947228277829. The reversal of 19947228277824 is 42877282274991.

The square root of 19947228277824 is 4466232.

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

19947228277824 is a `hidden beast` number, since 1 + 9 + 9 + 472 + 2 + 8 + 2 + 77 + 82 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 10459842652224 + 9487385625600 = 3234168^2 + 3080160^2 .

It is a Harshad number since it is a multiple of its sum of digits (72).

Its product of digits (455196672) is a multiple of the sum of its prime factors (196).

It is not an unprimeable number, because it can be changed into a prime (19947228277829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 188 ways as a sum of consecutive naturals, for example, 643458976689 + ... + 643458976719.

Almost surely, 2^{19947228277824} is an apocalyptic number.

19947228277824 is the 4466232-nd square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19947228277824

19947228277824 is an abundant number, since it is smaller than the sum of its proper divisors (46444873556325).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19947228277824 is an frugal number, since it uses more digits than its factorization.

19947228277824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196 (or 88 counting only the distinct ones).

The product of its digits is 455196672, while the sum is 72.

The spelling of 19947228277824 in words is "nineteen trillion, nine hundred forty-seven billion, two hundred twenty-eight million, two hundred seventy-seven thousand, eight hundred twenty-four".