1196378751681 has 81 divisors (see below), whose sum is σ = 1811738278467. Its totient is φ = 760753516320.

The previous prime is 1196378751613. The next prime is 1196378751727. The reversal of 1196378751681 is 1861578736911.

The square root of 1196378751681 is 1093791.

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

1196378751681 is a `hidden beast` number, since 1 + 1 + 9 + 6 + 37 + 8 + 7 + 516 + 81 = 666.

It can be written as a sum of positive squares in only one way, i.e., 38904012081 + 1157474739600 = 197241^2 + 1075860^2 .

It is not a de Polignac number, because 1196378751681 - 2⁷ = 1196378751553 is a prime.

It is a super-2 number, since 2×1196378751681² (a number of 25 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1196378751881) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 8607041310 + ... + 8607041448.

Almost surely, 2^{1196378751681} is an apocalyptic number.

1196378751681 is the 1093791-st square number.

1196378751681 is the 546896-th centered octagonal number.

It is an amenable number.

1196378751681 is a deficient number, since it is larger than the sum of its proper divisors (615359526786).

1196378751681 is an frugal number, since it uses more digits than its factorization.

1196378751681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 492 (or 246 counting only the distinct ones).

The product of its digits is 15240960, while the sum is 63.

The spelling of 1196378751681 in words is "one trillion, one hundred ninety-six billion, three hundred seventy-eight million, seven hundred fifty-one thousand, six hundred eighty-one".