671021 has 8 divisors (see below), whose sum is σ = 733824. Its totient is φ = 609840.

The previous prime is 671017. The next prime is 671029. The reversal of 671021 is 120176.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 671021 - 2² = 671017 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (671029) by changing a digit.

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, 560 + ... + 1286.

It is an arithmetic number, because the mean of its divisors is an integer number (91728).

2⁶⁷¹⁰²¹ is an apocalyptic number.

It is an amenable number.

671021 is a deficient number, since it is larger than the sum of its proper divisors (62803).

671021 is a wasteful number, since it uses less digits than its factorization.

671021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 811.

The product of its (nonzero) digits is 84, while the sum is 17.

The square root of 671021 is about 819.1587147800. The cubic root of 671021 is about 87.5478269146.

Adding to 671021 its reverse (120176), we get a palindrome (791197).

The spelling of 671021 in words is "six hundred seventy-one thousand, twenty-one".