1055666778 has 16 divisors (see below), whose sum is σ = 2118214560. Its totient is φ = 350742096.

The previous prime is 1055666767. The next prime is 1055666783. The reversal of 1055666778 is 8776665501.

It is a super-2 number, since 2×1055666778² = 2228864692345802568, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1055666778.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 284713 + ... + 288396.

It is an arithmetic number, because the mean of its divisors is an integer number (132388410).

Almost surely, 2^1055666778 is an apocalyptic number.

1055666778 is an abundant number, since it is smaller than the sum of its proper divisors (1062547782).

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

1055666778 is a wasteful number, since it uses less digits than its factorization.

1055666778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 573421.

The product of its (nonzero) digits is 2116800, while the sum is 51.

The square root of 1055666778 is about 32491.0261149136. The cubic root of 1055666778 is about 1018.2215510734.

The spelling of 1055666778 in words is "one billion, fifty-five million, six hundred sixty-six thousand, seven hundred seventy-eight".