1868887778 has 8 divisors (see below), whose sum is σ = 2815573980. Its totient is φ = 930363120.

The previous prime is 1868887777. The next prime is 1868887781. The reversal of 1868887778 is 8777888681.

It can be written as a sum of positive squares in 2 ways, for example, as 1390022089 + 478865689 = 37283^2 + 21883^2 .

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

It is not an unprimeable number, because it can be changed into a prime (1868887777) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2039813 + ... + 2040728.

Almost surely, 2^1868887778 is an apocalyptic number.

1868887778 is a deficient number, since it is larger than the sum of its proper divisors (946686202).

1868887778 is a wasteful number, since it uses less digits than its factorization.

1868887778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4080772.

The product of its digits is 67436544, while the sum is 68.

The square root of 1868887778 is about 43230.6347165988. The cubic root of 1868887778 is about 1231.7646642645.

The spelling of 1868887778 in words is "one billion, eight hundred sixty-eight million, eight hundred eighty-seven thousand, seven hundred seventy-eight".