630561 has 4 divisors (see below), whose sum is σ = 840752. Its totient is φ = 420372.

The previous prime is 630559. The next prime is 630577. The reversal of 630561 is 165036.

630561 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 630561 - 2¹ = 630559 is a prime.

It is a D-number.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (630521) 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, 105091 + ... + 105096.

It is an arithmetic number, because the mean of its divisors is an integer number (210188).

2⁶³⁰⁵⁶¹ is an apocalyptic number.

It is an amenable number.

630561 is a deficient number, since it is larger than the sum of its proper divisors (210191).

630561 is a wasteful number, since it uses less digits than its factorization.

630561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210190.

The product of its (nonzero) digits is 540, while the sum is 21.

The square root of 630561 is about 794.0787114638. The cubic root of 630561 is about 85.7516269840.

Adding to 630561 its reverse (165036), we get a palindrome (795597).

The spelling of 630561 in words is "six hundred thirty thousand, five hundred sixty-one".