2668778663 has 4 divisors (see below), whose sum is σ = 2668885008. Its totient is φ = 2668672320.

The previous prime is 2668778657. The next prime is 2668778687. The reversal of 2668778663 is 3668778662.

It is a happy number.

2668778663 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 2668778663 - 2⁸ = 2668778407 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2668778263) 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, 7703 + ... + 73463.

It is an arithmetic number, because the mean of its divisors is an integer number (667221252).

Almost surely, 2^2668778663 is an apocalyptic number.

2668778663 is a deficient number, since it is larger than the sum of its proper divisors (106345).

2668778663 is an equidigital number, since it uses as much as digits as its factorization.

2668778663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106344.

The product of its digits is 24385536, while the sum is 59.

The square root of 2668778663 is about 51660.2232186428. The cubic root of 2668778663 is about 1387.0885462124.

Subtracting 2668778663 from its reverse (3668778662), we obtain a palindrome (999999999).

The spelling of 2668778663 in words is "two billion, six hundred sixty-eight million, seven hundred seventy-eight thousand, six hundred sixty-three".