678882779 has 4 divisors (see below), whose sum is σ = 702292560. Its totient is φ = 655473000.

The previous prime is 678882769. The next prime is 678882791. The reversal of 678882779 is 977288876.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-678882779 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (678882769) 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, 11704847 + ... + 11704904.

It is an arithmetic number, because the mean of its divisors is an integer number (175573140).

Almost surely, 2^678882779 is an apocalyptic number.

678882779 is a deficient number, since it is larger than the sum of its proper divisors (23409781).

678882779 is a wasteful number, since it uses less digits than its factorization.

678882779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23409780.

The product of its digits is 18966528, while the sum is 62.

The square root of 678882779 is about 26055.3790799520. The cubic root of 678882779 is about 878.8840792237.

The spelling of 678882779 in words is "six hundred seventy-eight million, eight hundred eighty-two thousand, seven hundred seventy-nine".