1206381321864 has 24 divisors (see below), whose sum is σ = 3267282746910. Its totient is φ = 402127107264.

The previous prime is 1206381321863. The next prime is 1206381321913. The reversal of 1206381321864 is 4681231836021.

1206381321864 is a `hidden beast` number, since 1 + 2 + 0 + 638 + 1 + 3 + 2 + 1 + 8 + 6 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1159192448964 + 47188872900 = 1076658^2 + 217230^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is not an unprimeable number, because it can be changed into a prime (1206381321863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 8377647997 + ... + 8377648140.

Almost surely, 2^{1206381321864} is an apocalyptic number.

It is an amenable number.

1206381321864 is an abundant number, since it is smaller than the sum of its proper divisors (2060901425046).

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

1206381321864 is a wasteful number, since it uses less digits than its factorization.

1206381321864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16755296149 (or 16755296142 counting only the distinct ones).

The product of its (nonzero) digits is 331776, while the sum is 45.

The spelling of 1206381321864 in words is "one trillion, two hundred six billion, three hundred eighty-one million, three hundred twenty-one thousand, eight hundred sixty-four".