28718628 has 24 divisors (see below), whose sum is σ = 69924288. Its totient is φ = 9156576.

The previous prime is 28718621. The next prime is 28718639. The reversal of 28718628 is 82681782.

It is a self number, because there is not a number n which added to its sum of digits gives 28718628.

It is not an unprimeable number, because it can be changed into a prime (28718621) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 51751 + ... + 52302.

It is an arithmetic number, because the mean of its divisors is an integer number (2913512).

Almost surely, 2^28718628 is an apocalyptic number.

It is an amenable number.

28718628 is an abundant number, since it is smaller than the sum of its proper divisors (41205660).

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

28718628 is a wasteful number, since it uses less digits than its factorization.

28718628 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104083 (or 104081 counting only the distinct ones).

The product of its digits is 86016, while the sum is 42.

The square root of 28718628 is about 5358.9763947978. The cubic root of 28718628 is about 306.2348148517.

It can be divided in two parts, 287 and 18628, that added together give a triangular number (18915 = T₁₉₄).

The spelling of 28718628 in words is "twenty-eight million, seven hundred eighteen thousand, six hundred twenty-eight".