1158778566 has 48 divisors (see below), whose sum is σ = 2754844560. Its totient is φ = 349104960.

The previous prime is 1158778553. The next prime is 1158778589. The reversal of 1158778566 is 6658778511.

1158778566 is a `hidden beast` number, since 1 + 1 + 5 + 8 + 7 + 78 + 566 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17340 + ... + 51168.

It is an arithmetic number, because the mean of its divisors is an integer number (57392595).

Almost surely, 2^1158778566 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1158778566, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1377422280).

1158778566 is an abundant number, since it is smaller than the sum of its proper divisors (1596065994).

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

1158778566 is a wasteful number, since it uses less digits than its factorization.

1158778566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34021 (or 34018 counting only the distinct ones).

The product of its digits is 2822400, while the sum is 54.

The square root of 1158778566 is about 34040.8367405973. The cubic root of 1158778566 is about 1050.3486570032.

Subtracting 1158778566 from its reverse (6658778511), we obtain a palindrome (5499999945).

The spelling of 1158778566 in words is "one billion, one hundred fifty-eight million, seven hundred seventy-eight thousand, five hundred sixty-six".