28643394 has 32 divisors (see below), whose sum is σ = 62112960. Its totient is φ = 8753472.

The previous prime is 28643369. The next prime is 28643399. The reversal of 28643394 is 49334682.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (28643399) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11077 + ... + 13415.

It is an arithmetic number, because the mean of its divisors is an integer number (1941030).

Almost surely, 2^28643394 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28643394, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31056480).

28643394 is an abundant number, since it is smaller than the sum of its proper divisors (33469566).

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

28643394 is a wasteful number, since it uses less digits than its factorization.

28643394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2514.

The product of its digits is 124416, while the sum is 39.

The square root of 28643394 is about 5351.9523540480. The cubic root of 28643394 is about 305.9671672236.

The spelling of 28643394 in words is "twenty-eight million, six hundred forty-three thousand, three hundred ninety-four".