630021 has 16 divisors (see below), whose sum is σ = 1011200. Its totient is φ = 340848.

The previous prime is 630017. The next prime is 630023. The reversal of 630021 is 120036.

It is not a de Polignac number, because 630021 - 2² = 630017 is a prime.

It is a Duffinian number.

630021 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 629979 and 630006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (630023) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 391 + ... + 1188.

It is an arithmetic number, because the mean of its divisors is an integer number (63200).

2⁶³⁰⁰²¹ is an apocalyptic number.

It is an amenable number.

630021 is a deficient number, since it is larger than the sum of its proper divisors (381179).

630021 is a wasteful number, since it uses less digits than its factorization.

630021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1608.

The product of its (nonzero) digits is 36, while the sum is 12.

The square root of 630021 is about 793.7386219657. The cubic root of 630021 is about 85.7271413258.

Adding to 630021 its reverse (120036), we get a palindrome (750057).

The spelling of 630021 in words is "six hundred thirty thousand, twenty-one".