670021 has 8 divisors (see below), whose sum is σ = 774144. Its totient is φ = 573120.

The previous prime is 670001. The next prime is 670031. The reversal of 670021 is 120076.

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 670021 - 2⁵ = 669989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 669977 and 670004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (670001) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1605 + ... + 1978.

It is an arithmetic number, because the mean of its divisors is an integer number (96768).

2⁶⁷⁰⁰²¹ is an apocalyptic number.

It is an amenable number.

670021 is a deficient number, since it is larger than the sum of its proper divisors (104123).

670021 is a wasteful number, since it uses less digits than its factorization.

670021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3611.

The product of its (nonzero) digits is 84, while the sum is 16.

The square root of 670021 is about 818.5481048784. The cubic root of 670021 is about 87.5043154334.

Adding to 670021 its reverse (120076), we get a palindrome (790097).

Subtracting from 670021 its reverse (120076), we obtain a palindrome (549945).

The spelling of 670021 in words is "six hundred seventy thousand, twenty-one".