678121858 has 8 divisors (see below), whose sum is σ = 1017417852. Its totient is φ = 338982576.

The previous prime is 678121849. The next prime is 678121879. The reversal of 678121858 is 858121876.

It can be written as a sum of positive squares in 2 ways, for example, as 559464409 + 118657449 = 23653^2 + 10893^2 .

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

It is an alternating number because its digits alternate between even and odd.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27685 + ... + 46072.

Almost surely, 2^678121858 is an apocalyptic number.

678121858 is a deficient number, since it is larger than the sum of its proper divisors (339295994).

678121858 is a wasteful number, since it uses less digits than its factorization.

678121858 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78356.

The product of its digits is 215040, while the sum is 46.

The square root of 678121858 is about 26040.7729915992. The cubic root of 678121858 is about 878.5555927812. Note that the first 4 decimals are identical.

The spelling of 678121858 in words is "six hundred seventy-eight million, one hundred twenty-one thousand, eight hundred fifty-eight".