628978 has 8 divisors (see below), whose sum is σ = 1078272. Its totient is φ = 269556.

The previous prime is 628973. The next prime is 628993. The reversal of 628978 is 879826.

628978 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a super-2 number, since 2×628978² = 791226648968, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 628978.

It is not an unprimeable number, because it can be changed into a prime (628973) by changing a digit.

628978 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22450 + ... + 22477.

It is an arithmetic number, because the mean of its divisors is an integer number (134784).

2⁶²⁸⁹⁷⁸ is an apocalyptic number.

628978 is a deficient number, since it is larger than the sum of its proper divisors (449294).

628978 is a wasteful number, since it uses less digits than its factorization.

628978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44936.

The product of its digits is 48384, while the sum is 40.

The square root of 628978 is about 793.0813325252. The cubic root of 628978 is about 85.6798080913.

The spelling of 628978 in words is "six hundred twenty-eight thousand, nine hundred seventy-eight".