671812 has 6 divisors (see below), whose sum is σ = 1175678. Its totient is φ = 335904.

The previous prime is 671791. The next prime is 671831. The reversal of 671812 is 218176.

It can be written as a sum of positive squares in only one way, i.e., 662596 + 9216 = 814^2 + 96^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83973 + ... + 83980.

2⁶⁷¹⁸¹² is an apocalyptic number.

It is an amenable number.

671812 is a deficient number, since it is larger than the sum of its proper divisors (503866).

671812 is a wasteful number, since it uses less digits than its factorization.

671812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167957 (or 167955 counting only the distinct ones).

The product of its digits is 672, while the sum is 25.

The square root of 671812 is about 819.6413849971. The cubic root of 671812 is about 87.5822138852.

Adding to 671812 its reverse (218176), we get a palindrome (889988).

The spelling of 671812 in words is "six hundred seventy-one thousand, eight hundred twelve".