678111657 has 8 divisors (see below), whose sum is σ = 957334176. Its totient is φ = 425481792.

The previous prime is 678111641. The next prime is 678111671. The reversal of 678111657 is 756111876.

It is a happy number.

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

It is not a de Polignac number, because 678111657 - 2⁴ = 678111641 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (678111697) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6648103 + ... + 6648204.

It is an arithmetic number, because the mean of its divisors is an integer number (119666772).

Almost surely, 2^678111657 is an apocalyptic number.

It is an amenable number.

678111657 is a deficient number, since it is larger than the sum of its proper divisors (279222519).

678111657 is a wasteful number, since it uses less digits than its factorization.

678111657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13296327.

The product of its digits is 70560, while the sum is 42.

The square root of 678111657 is about 26040.5771249410. The cubic root of 678111657 is about 878.5511873829.

The spelling of 678111657 in words is "six hundred seventy-eight million, one hundred eleven thousand, six hundred fifty-seven".