1266749778 has 16 divisors (see below), whose sum is σ = 2895428160. Its totient is φ = 361928496.

The previous prime is 1266749707. The next prime is 1266749791. The reversal of 1266749778 is 8779476621.

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 7 ways as a sum of consecutive naturals, for example, 15080313 + ... + 15080396.

It is an arithmetic number, because the mean of its divisors is an integer number (180964260).

Almost surely, 2^1266749778 is an apocalyptic number.

1266749778 is an abundant number, since it is smaller than the sum of its proper divisors (1628678382).

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

1266749778 is a wasteful number, since it uses less digits than its factorization.

1266749778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30160721.

The product of its digits is 7112448, while the sum is 57.

The square root of 1266749778 is about 35591.4284343857. The cubic root of 1266749778 is about 1082.0075195111.

The spelling of 1266749778 in words is "one billion, two hundred sixty-six million, seven hundred forty-nine thousand, seven hundred seventy-eight".