3145728 has 42 divisors (see below), whose sum is σ = 8388604. Its totient is φ = 1048576.

The previous prime is 3145721. The next prime is 3145739. The reversal of 3145728 is 8275413.

It is a Jordan-Polya number, since it can be written as 4! ⋅ (2!)¹⁷.

Its product of digits (6720) is a multiple of the sum of its prime divisors (5).

It is a nialpdrome in base 2, base 4 and base 16.

It is a zygodrome in base 2.

It is a junction number, because it is equal to n+sod(n) for n = 3145695 and 3145704.

It is not an unprimeable number, because it can be changed into a prime (3145721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (2) of ones.

In principle, a polygon with 3145728 sides can be constructed with ruler and compass.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1048575 + 1048576 + 1048577.

Almost surely, 2^3145728 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 3145728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4194302).

3145728 is an abundant number, since it is smaller than the sum of its proper divisors (5242876).

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

3145728 is an frugal number, since it uses more digits than its factorization.

3145728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43 (or 5 counting only the distinct ones).

The product of its digits is 6720, while the sum is 30.

The square root of 3145728 is about 1773.6200269505. The cubic root of 3145728 is about 146.5234230468.

The spelling of 3145728 in words is "three million, one hundred forty-five thousand, seven hundred twenty-eight".