2116765778 has 8 divisors (see below), whose sum is σ = 3361922172. Its totient is φ = 996125056.

The previous prime is 2116765771. The next prime is 2116765787. The reversal of 2116765778 is 8775676112.

It can be written as a sum of positive squares in 2 ways, for example, as 2045481529 + 71284249 = 45227^2 + 8443^2 .

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

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2116765771) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31128875 + ... + 31128942.

Almost surely, 2^2116765778 is an apocalyptic number.

2116765778 is a deficient number, since it is larger than the sum of its proper divisors (1245156394).

2116765778 is a wasteful number, since it uses less digits than its factorization.

2116765778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62257836.

The product of its digits is 987840, while the sum is 50.

The square root of 2116765778 is about 46008.3229209672. The cubic root of 2116765778 is about 1283.9780573076.

The spelling of 2116765778 in words is "two billion, one hundred sixteen million, seven hundred sixty-five thousand, seven hundred seventy-eight".