28219728 has 40 divisors (see below), whose sum is σ = 77191488. Its totient is φ = 8852992.

The previous prime is 28219727. The next prime is 28219753. The reversal of 28219728 is 82791282.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28219727) 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, 16476 + ... + 18107.

Almost surely, 2^28219728 is an apocalyptic number.

It is an amenable number.

28219728 is an abundant number, since it is smaller than the sum of its proper divisors (48971760).

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

28219728 is a wasteful number, since it uses less digits than its factorization.

28219728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34611 (or 34605 counting only the distinct ones).

The product of its digits is 32256, while the sum is 39.

The square root of 28219728 is about 5312.2243928509. The cubic root of 28219728 is about 304.4511422604.

The spelling of 28219728 in words is "twenty-eight million, two hundred nineteen thousand, seven hundred twenty-eight".