678706628 has 6 divisors (see below), whose sum is σ = 1187736606. Its totient is φ = 339353312.

The previous prime is 678706627. The next prime is 678706729. The reversal of 678706628 is 826607876.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 542330944 + 136375684 = 23288^2 + 11678^2 .

It is a super-2 number, since 2×678706628² = 921285373782260768, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (678706621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84838325 + ... + 84838332.

It is an arithmetic number, because the mean of its divisors is an integer number (197956101).

Almost surely, 2^678706628 is an apocalyptic number.

It is an amenable number.

678706628 is a deficient number, since it is larger than the sum of its proper divisors (509029978).

678706628 is a wasteful number, since it uses less digits than its factorization.

678706628 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 169676661 (or 169676659 counting only the distinct ones).

The product of its (nonzero) digits is 1354752, while the sum is 50.

The square root of 678706628 is about 26051.9985413787. The cubic root of 678706628 is about 878.8080574095.

The spelling of 678706628 in words is "six hundred seventy-eight million, seven hundred six thousand, six hundred twenty-eight".