671628 has 24 divisors (see below), whose sum is σ = 1586032. Its totient is φ = 221184.

The previous prime is 671609. The next prime is 671633. The reversal of 671628 is 826176.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 671595 and 671604.

It is an unprimeable number.

671628 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 876 + ... + 1452.

2⁶⁷¹⁶²⁸ is an apocalyptic number.

It is an amenable number.

671628 is an abundant number, since it is smaller than the sum of its proper divisors (914404).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

671628 is a wasteful number, since it uses less digits than its factorization.

671628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 681 (or 679 counting only the distinct ones).

The product of its digits is 4032, while the sum is 30.

The square root of 671628 is about 819.5291331002. The cubic root of 671628 is about 87.5742173034.

The spelling of 671628 in words is "six hundred seventy-one thousand, six hundred twenty-eight".