678266681 has 4 divisors (see below), whose sum is σ = 678323712. Its totient is φ = 678209652.

The previous prime is 678266669. The next prime is 678266683. The reversal of 678266681 is 186662876.

It is a happy number.

678266681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-678266681 is a prime.

It is a super-2 number, since 2×678266681² = 920091381109511522, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (678266683) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3161 + ... + 36966.

It is an arithmetic number, because the mean of its divisors is an integer number (169580928).

Almost surely, 2^678266681 is an apocalyptic number.

It is an amenable number.

678266681 is a deficient number, since it is larger than the sum of its proper divisors (57031).

678266681 is a wasteful number, since it uses less digits than its factorization.

678266681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57030.

The product of its digits is 1161216, while the sum is 50.

The square root of 678266681 is about 26043.5535401757. The cubic root of 678266681 is about 878.6181311969.

The spelling of 678266681 in words is "six hundred seventy-eight million, two hundred sixty-six thousand, six hundred eighty-one".