28280539 has 8 divisors (see below), whose sum is σ = 33435360. Its totient is φ = 23404416.

The previous prime is 28280491. The next prime is 28280563. The reversal of 28280539 is 93508282.

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

It is not a de Polignac number, because 28280539 - 2¹³ = 28272347 is a prime.

It is a super-2 number, since 2×28280539² = 1599577772261042, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 28280498 and 28280507.

It is not an unprimeable number, because it can be changed into a prime (28280599) 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, 69454 + ... + 69859.

It is an arithmetic number, because the mean of its divisors is an integer number (4179420).

Almost surely, 2^28280539 is an apocalyptic number.

28280539 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

28280539 is a deficient number, since it is larger than the sum of its proper divisors (5154821).

28280539 is a wasteful number, since it uses less digits than its factorization.

28280539 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139349.

The product of its (nonzero) digits is 34560, while the sum is 37.

The square root of 28280539 is about 5317.9449978352. The cubic root of 28280539 is about 304.6696737272.

The spelling of 28280539 in words is "twenty-eight million, two hundred eighty thousand, five hundred thirty-nine".