28328578 has 4 divisors (see below), whose sum is σ = 42492870. Its totient is φ = 14164288.

The previous prime is 28328551. The next prime is 28328591. The reversal of 28328578 is 87582382.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 21687649 + 6640929 = 4657^2 + 2577^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7082143 + ... + 7082146.

Almost surely, 2^28328578 is an apocalyptic number.

28328578 is a deficient number, since it is larger than the sum of its proper divisors (14164292).

28328578 is a wasteful number, since it uses less digits than its factorization.

28328578 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14164291.

The product of its digits is 215040, while the sum is 43.

The square root of 28328578 is about 5322.4597696930. The cubic root of 28328578 is about 304.8420861302.

The spelling of 28328578 in words is "twenty-eight million, three hundred twenty-eight thousand, five hundred seventy-eight".