678877805 has 4 divisors (see below), whose sum is σ = 814653372. Its totient is φ = 543102240.

The previous prime is 678877799. The next prime is 678877811. The reversal of 678877805 is 508778876.

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

It is an interprime number because it is at equal distance from previous prime (678877799) and next prime (678877811).

It can be written as a sum of positive squares in 2 ways, for example, as 499880164 + 178997641 = 22358^2 + 13379^2 .

It is not a de Polignac number, because 678877805 - 2⁶ = 678877741 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 67887776 + ... + 67887785.

It is an arithmetic number, because the mean of its divisors is an integer number (203663343).

Almost surely, 2^678877805 is an apocalyptic number.

It is an amenable number.

678877805 is a deficient number, since it is larger than the sum of its proper divisors (135775567).

678877805 is a wasteful number, since it uses less digits than its factorization.

678877805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135775566.

The product of its (nonzero) digits is 5268480, while the sum is 56.

The square root of 678877805 is about 26055.2836292373. The cubic root of 678877805 is about 878.8819327658.

The spelling of 678877805 in words is "six hundred seventy-eight million, eight hundred seventy-seven thousand, eight hundred five".