1266123778 has 8 divisors (see below), whose sum is σ = 1899574272. Its totient is φ = 632932356.

The previous prime is 1266123763. The next prime is 1266123787. The reversal of 1266123778 is 8773216621.

It is a sphenic number, since it is the product of 3 distinct primes.

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 3 ways as a sum of consecutive naturals, for example, 52050 + ... + 72397.

It is an arithmetic number, because the mean of its divisors is an integer number (237446784).

Almost surely, 2^1266123778 is an apocalyptic number.

1266123778 is a deficient number, since it is larger than the sum of its proper divisors (633450494).

1266123778 is a wasteful number, since it uses less digits than its factorization.

1266123778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129536.

The product of its digits is 169344, while the sum is 43.

The square root of 1266123778 is about 35582.6330953739. The cubic root of 1266123778 is about 1081.8292553360.

The spelling of 1266123778 in words is "one billion, two hundred sixty-six million, one hundred twenty-three thousand, seven hundred seventy-eight".