678651851 has 4 divisors (see below), whose sum is σ = 678809712. Its totient is φ = 678493992.

The previous prime is 678651773. The next prime is 678651863. The reversal of 678651851 is 158156876.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 678651851 - 2²² = 674457547 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 678651796 and 678651805.

It is not an unprimeable number, because it can be changed into a prime (678656851) by changing a digit.

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, 72296 + ... + 81141.

It is an arithmetic number, because the mean of its divisors is an integer number (169702428).

Almost surely, 2^678651851 is an apocalyptic number.

678651851 is a deficient number, since it is larger than the sum of its proper divisors (157861).

678651851 is a wasteful number, since it uses less digits than its factorization.

678651851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157860.

The product of its digits is 403200, while the sum is 47.

The square root of 678651851 is about 26050.9472188633. The cubic root of 678651851 is about 878.7844145167.

The spelling of 678651851 in words is "six hundred seventy-eight million, six hundred fifty-one thousand, eight hundred fifty-one".