731628 has 18 divisors (see below), whose sum is σ = 1849484. Its totient is φ = 243864.

The previous prime is 731623. The next prime is 731639. The reversal of 731628 is 826137.

731628 is a `hidden beast` number, since 7 + 31 + 628 = 666.

It is a tau number, because it is divible by the number of its divisors (18).

It is not an unprimeable number, because it can be changed into a prime (731623) by changing a digit.

731628 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 10126 + ... + 10197.

2⁷³¹⁶²⁸ is an apocalyptic number.

It is an amenable number.

731628 is an abundant number, since it is smaller than the sum of its proper divisors (1117856).

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

731628 is a wasteful number, since it uses less digits than its factorization.

731628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20333 (or 20328 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 731628 is about 855.3525588902. The cubic root of 731628 is about 90.1080184520.

The spelling of 731628 in words is "seven hundred thirty-one thousand, six hundred twenty-eight".