1228867778 has 4 divisors (see below), whose sum is σ = 1843301670. Its totient is φ = 614433888.

The previous prime is 1228867771. The next prime is 1228867789. The reversal of 1228867778 is 8777688221.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 1169161249 + 59706529 = 34193^2 + 7727^2 .

It is not an unprimeable number, because it can be changed into a prime (1228867771) by changing a digit.

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 as a sum of consecutive naturals, namely, 307216943 + ... + 307216946.

Almost surely, 2^1228867778 is an apocalyptic number.

1228867778 is a deficient number, since it is larger than the sum of its proper divisors (614433892).

1228867778 is an equidigital number, since it uses as much as digits as its factorization.

1228867778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 614433891.

The product of its digits is 4214784, while the sum is 56.

The square root of 1228867778 is about 35055.2104258411. The cubic root of 1228867778 is about 1071.1124128365.

The spelling of 1228867778 in words is "one billion, two hundred twenty-eight million, eight hundred sixty-seven thousand, seven hundred seventy-eight".