630891 has 6 divisors (see below), whose sum is σ = 911300. Its totient is φ = 420588.

The previous prime is 630871. The next prime is 630893. The reversal of 630891 is 198036.

It is not a de Polignac number, because 630891 - 2⁶ = 630827 is a prime.

It is a Duffinian number.

630891 is a modest number, since divided by 891 gives 63 as remainder.

It is not an unprimeable number, because it can be changed into a prime (630893) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 35041 + ... + 35058.

2⁶³⁰⁸⁹¹ is an apocalyptic number.

630891 is a deficient number, since it is larger than the sum of its proper divisors (280409).

630891 is a wasteful number, since it uses less digits than its factorization.

630891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70105 (or 70102 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 630891 is about 794.2864722504. The cubic root of 630891 is about 85.7665835606.

It can be divided in two parts, 630 and 891, that added together give a square (1521 = 39²).

The spelling of 630891 in words is "six hundred thirty thousand, eight hundred ninety-one".