1211857165768 has 32 divisors (see below), whose sum is σ = 2329782771960. Its totient is φ = 590608811520.

The previous prime is 1211857165759. The next prime is 1211857165769. The reversal of 1211857165768 is 8675617581121.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 980016841764 + 231840324004 = 989958^2 + 481498^2 .

It is not an unprimeable number, because it can be changed into a prime (1211857165769) 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 7 ways as a sum of consecutive naturals, for example, 1331655 + ... + 2048662.

Almost surely, 2^{1211857165768} is an apocalyptic number.

It is an amenable number.

1211857165768 is a deficient number, since it is larger than the sum of its proper divisors (1117925606192).

1211857165768 is a wasteful number, since it uses less digits than its factorization.

1211857165768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3381457 (or 3381453 counting only the distinct ones).

The product of its digits is 5644800, while the sum is 58.

The spelling of 1211857165768 in words is "one trillion, two hundred eleven billion, eight hundred fifty-seven million, one hundred sixty-five thousand, seven hundred sixty-eight".