28780539 has 8 divisors (see below), whose sum is σ = 38733120. Its totient is φ = 19007496.

The previous prime is 28780519. The next prime is 28780547. The reversal of 28780539 is 93508782.

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

It is not a de Polignac number, because 28780539 - 2¹² = 28776443 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28780539.

It is not an unprimeable number, because it can be changed into a prime (28780519) 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, 44509 + ... + 45150.

It is an arithmetic number, because the mean of its divisors is an integer number (4841640).

Almost surely, 2^28780539 is an apocalyptic number.

28780539 is a deficient number, since it is larger than the sum of its proper divisors (9952581).

28780539 is a wasteful number, since it uses less digits than its factorization.

28780539 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89769.

The product of its (nonzero) digits is 120960, while the sum is 42.

The square root of 28780539 is about 5364.7496679715. The cubic root of 28780539 is about 306.4547150490.

The spelling of 28780539 in words is "twenty-eight million, seven hundred eighty thousand, five hundred thirty-nine".