28394688 has 112 divisors (see below), whose sum is σ = 88335104. Its totient is φ = 7879680.

The previous prime is 28394687. The next prime is 28394689. The reversal of 28394688 is 88649382.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (28394687) and next prime (28394689).

It is a tau number, because it is divible by the number of its divisors (112).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28394687) 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, 49443 + ... + 50013.

Almost surely, 2^28394688 is an apocalyptic number.

28394688 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28394688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44167552).

28394688 is an abundant number, since it is smaller than the sum of its proper divisors (59940416).

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

28394688 is a wasteful number, since it uses less digits than its factorization.

28394688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 630 (or 620 counting only the distinct ones).

The product of its digits is 663552, while the sum is 48.

The square root of 28394688 is about 5328.6666249635. Note that the first 4 decimals coincide. The cubic root of 28394688 is about 305.0790371177.

It can be divided in two parts, 28 and 394688, that added together give a triangular number (394716 = T₈₈₈).

The spelling of 28394688 in words is "twenty-eight million, three hundred ninety-four thousand, six hundred eighty-eight".