3128728 has 16 divisors (see below), whose sum is σ = 5924880. Its totient is φ = 1548768.

The previous prime is 3128701. The next prime is 3128729. The reversal of 3128728 is 8278213.

It is a self number, because there is not a number n which added to its sum of digits gives 3128728.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3128729) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1075 + ... + 2722.

It is an arithmetic number, because the mean of its divisors is an integer number (370305).

Almost surely, 2^3128728 is an apocalyptic number.

It is an amenable number.

3128728 is a deficient number, since it is larger than the sum of its proper divisors (2796152).

3128728 is a wasteful number, since it uses less digits than its factorization.

3128728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3906 (or 3902 counting only the distinct ones).

The product of its digits is 5376, while the sum is 31.

The square root of 3128728 is about 1768.8210763104. The cubic root of 3128728 is about 146.2590010775.

The spelling of 3128728 in words is "three million, one hundred twenty-eight thousand, seven hundred twenty-eight".