671858 has 8 divisors (see below), whose sum is σ = 1099440. Its totient is φ = 305380.

The previous prime is 671851. The next prime is 671887. The reversal of 671858 is 858176.

It is a happy number.

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

It is an Ulam number.

It is a Curzon number.

It is a plaindrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (671851) by changing a digit.

671858 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 (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15248 + ... + 15291.

It is an arithmetic number, because the mean of its divisors is an integer number (137430).

2⁶⁷¹⁸⁵⁸ is an apocalyptic number.

671858 is a deficient number, since it is larger than the sum of its proper divisors (427582).

671858 is a wasteful number, since it uses less digits than its factorization.

671858 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30552.

The product of its digits is 13440, while the sum is 35.

The square root of 671858 is about 819.6694455694. The cubic root of 671858 is about 87.5842128025.

It can be divided in two parts, 6718 and 58, that added together give a palindrome (6776).

The spelling of 671858 in words is "six hundred seventy-one thousand, eight hundred fifty-eight".