671345 has 4 divisors (see below), whose sum is σ = 805620. Its totient is φ = 537072.

The previous prime is 671339. The next prime is 671353. The reversal of 671345 is 543176.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 456976 + 214369 = 676^2 + 463^2 .

It is a cyclic number.

It is not a de Polignac number, because 671345 - 2¹⁰ = 670321 is a prime.

It is an unprimeable 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 3 ways as a sum of consecutive naturals, for example, 67130 + ... + 67139.

It is an arithmetic number, because the mean of its divisors is an integer number (201405).

2⁶⁷¹³⁴⁵ is an apocalyptic number.

It is an amenable number.

671345 is a deficient number, since it is larger than the sum of its proper divisors (134275).

671345 is a wasteful number, since it uses less digits than its factorization.

671345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134274.

The product of its digits is 2520, while the sum is 26.

The square root of 671345 is about 819.3564547863. The cubic root of 671345 is about 87.5619153618.

The spelling of 671345 in words is "six hundred seventy-one thousand, three hundred forty-five".