28578139 has 8 divisors (see below), whose sum is σ = 30686688. Its totient is φ = 26517120.

The previous prime is 28578133. The next prime is 28578161. The reversal of 28578139 is 93187582.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28578139 - 2³ = 28578131 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28578095 and 28578104.

It is not an unprimeable number, because it can be changed into a prime (28578131) 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, 10632 + ... + 13045.

It is an arithmetic number, because the mean of its divisors is an integer number (3835836).

Almost surely, 2^28578139 is an apocalyptic number.

28578139 is a deficient number, since it is larger than the sum of its proper divisors (2108549).

28578139 is a wasteful number, since it uses less digits than its factorization.

28578139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23765.

The product of its digits is 120960, while the sum is 43.

The square root of 28578139 is about 5345.8525045123. The cubic root of 28578139 is about 305.7346404413.

The spelling of 28578139 in words is "twenty-eight million, five hundred seventy-eight thousand, one hundred thirty-nine".