678765657 has 4 divisors (see below), whose sum is σ = 905020880. Its totient is φ = 452510436.

The previous prime is 678765623. The next prime is 678765679. The reversal of 678765657 is 756567876.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 678765657 - 2¹⁴ = 678749273 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 678765597 and 678765606.

It is not an unprimeable number, because it can be changed into a prime (678765257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 113127607 + ... + 113127612.

It is an arithmetic number, because the mean of its divisors is an integer number (226255220).

Almost surely, 2^678765657 is an apocalyptic number.

It is an amenable number.

678765657 is a deficient number, since it is larger than the sum of its proper divisors (226255223).

678765657 is a wasteful number, since it uses less digits than its factorization.

678765657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 226255222.

The product of its digits is 14817600, while the sum is 57.

The square root of 678765657 is about 26053.1314240726. The cubic root of 678765657 is about 878.8335341299.

The spelling of 678765657 in words is "six hundred seventy-eight million, seven hundred sixty-five thousand, six hundred fifty-seven".