671997 has 4 divisors (see below), whose sum is σ = 896000. Its totient is φ = 447996.

The previous prime is 671981. The next prime is 671999. The reversal of 671997 is 799176.

671997 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 671997 - 2⁴ = 671981 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (671999) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 111997 + ... + 112002.

It is an arithmetic number, because the mean of its divisors is an integer number (224000).

2⁶⁷¹⁹⁹⁷ is an apocalyptic number.

It is an amenable number.

671997 is a deficient number, since it is larger than the sum of its proper divisors (224003).

671997 is a wasteful number, since it uses less digits than its factorization.

671997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 224002.

The product of its digits is 23814, while the sum is 39.

The square root of 671997 is about 819.7542314621. The cubic root of 671997 is about 87.5902524547.

The spelling of 671997 in words is "six hundred seventy-one thousand, nine hundred ninety-seven".