631128 has 16 divisors (see below), whose sum is σ = 1577880. Its totient is φ = 210368.

The previous prime is 631121. The next prime is 631133. The reversal of 631128 is 821136.

631128 is nontrivially palindromic in base 11.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (631121) by changing a digit.

631128 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13125 + ... + 13172.

2⁶³¹¹²⁸ is an apocalyptic number.

It is an amenable number.

631128 is an abundant number, since it is smaller than the sum of its proper divisors (946752).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

631128 is a wasteful number, since it uses less digits than its factorization.

631128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26306 (or 26302 counting only the distinct ones).

The product of its digits is 288, while the sum is 21.

The square root of 631128 is about 794.4356487470. The cubic root of 631128 is about 85.7773218844. Note that the first 3 decimals are identical.

The spelling of 631128 in words is "six hundred thirty-one thousand, one hundred twenty-eight".