724128 has 48 divisors (see below), whose sum is σ = 2005920. Its totient is φ = 228096.

The previous prime is 724123. The next prime is 724153. The reversal of 724128 is 821427.

It is a tau number, because it is divible by the number of its divisors (48).

It is a super-2 number, since 2×724128² = 1048722720768, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 724098 and 724107.

It is not an unprimeable number, because it can be changed into a prime (724121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1626 + ... + 2022.

It is an arithmetic number, because the mean of its divisors is an integer number (41790).

2⁷²⁴¹²⁸ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 724128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1002960).

724128 is an abundant number, since it is smaller than the sum of its proper divisors (1281792).

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

724128 is a wasteful number, since it uses less digits than its factorization.

724128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 429 (or 421 counting only the distinct ones).

The product of its digits is 896, while the sum is 24.

The square root of 724128 is about 850.9571082023. The cubic root of 724128 is about 89.7990578652.

The spelling of 724128 in words is "seven hundred twenty-four thousand, one hundred twenty-eight".