1266221188 has 12 divisors (see below), whose sum is σ = 2216688012. Its totient is φ = 632881760.

The previous prime is 1266221107. The next prime is 1266221233. The reversal of 1266221188 is 8811226621.

It can be written as a sum of positive squares in 2 ways, for example, as 731594304 + 534626884 = 27048^2 + 23122^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 44443 + ... + 67138.

It is an arithmetic number, because the mean of its divisors is an integer number (184724001).

Almost surely, 2^1266221188 is an apocalyptic number.

It is an amenable number.

1266221188 is a deficient number, since it is larger than the sum of its proper divisors (950466824).

1266221188 is a wasteful number, since it uses less digits than its factorization.

1266221188 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114422 (or 114420 counting only the distinct ones).

The product of its digits is 18432, while the sum is 37.

The square root of 1266221188 is about 35584.0018547661. The cubic root of 1266221188 is about 1081.8569983543.

The spelling of 1266221188 in words is "one billion, two hundred sixty-six million, two hundred twenty-one thousand, one hundred eighty-eight".