28728612 has 36 divisors (see below), whose sum is σ = 79222416. Its totient is φ = 8705520.

The previous prime is 28728607. The next prime is 28728631. The reversal of 28728612 is 21682782.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nialpdrome in base 12.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 35878 + ... + 36669.

Almost surely, 2^28728612 is an apocalyptic number.

28728612 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

28728612 is an abundant number, since it is smaller than the sum of its proper divisors (50493804).

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

28728612 is a wasteful number, since it uses less digits than its factorization.

28728612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72568 (or 72563 counting only the distinct ones).

The product of its digits is 21504, while the sum is 36.

The square root of 28728612 is about 5359.9078350285. The cubic root of 28728612 is about 306.2702981409.

The spelling of 28728612 in words is "twenty-eight million, seven hundred twenty-eight thousand, six hundred twelve".