1188778866 has 64 divisors (see below), whose sum is σ = 2649891456. Its totient is φ = 352512000.

The previous prime is 1188778861. The next prime is 1188778867. The reversal of 1188778866 is 6688778811.

It is a zygodrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (1188778861) 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 31 ways as a sum of consecutive naturals, for example, 659166 + ... + 660966.

It is an arithmetic number, because the mean of its divisors is an integer number (41404554).

Almost surely, 2^1188778866 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1188778866, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1324945728).

1188778866 is an abundant number, since it is smaller than the sum of its proper divisors (1461112590).

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

1188778866 is a wasteful number, since it uses less digits than its factorization.

1188778866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2027.

The product of its digits is 7225344, while the sum is 60.

The square root of 1188778866 is about 34478.6726252621. The cubic root of 1188778866 is about 1059.3359035945.

Subtracting 1188778866 from its reverse (6688778811), we obtain a palindrome (5499999945).

The spelling of 1188778866 in words is "one billion, one hundred eighty-eight million, seven hundred seventy-eight thousand, eight hundred sixty-six".