28128394 has 8 divisors (see below), whose sum is σ = 48220128. Its totient is φ = 12055020.

The previous prime is 28128391. The next prime is 28128449. The reversal of 28128394 is 49382182.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (28128391) 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, 1004572 + ... + 1004599.

It is an arithmetic number, because the mean of its divisors is an integer number (6027516).

Almost surely, 2^28128394 is an apocalyptic number.

28128394 is a deficient number, since it is larger than the sum of its proper divisors (20091734).

28128394 is a wasteful number, since it uses less digits than its factorization.

28128394 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2009180.

The product of its digits is 27648, while the sum is 37.

The square root of 28128394 is about 5303.6208386347. The cubic root of 28128394 is about 304.1223321717.

The spelling of 28128394 in words is "twenty-eight million, one hundred twenty-eight thousand, three hundred ninety-four".