28966139 has 4 divisors (see below), whose sum is σ = 29096256. Its totient is φ = 28836024.

The previous prime is 28966129. The next prime is 28966169. The reversal of 28966139 is 93166982.

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

It is a cyclic number.

It is not a de Polignac number, because 28966139 - 2⁴ = 28966123 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28966139.

It is not an unprimeable number, because it can be changed into a prime (28966129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64724 + ... + 65169.

It is an arithmetic number, because the mean of its divisors is an integer number (7274064).

Almost surely, 2^28966139 is an apocalyptic number.

28966139 is a deficient number, since it is larger than the sum of its proper divisors (130117).

28966139 is a wasteful number, since it uses less digits than its factorization.

28966139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130116.

The product of its digits is 139968, while the sum is 44.

The square root of 28966139 is about 5382.0199739503. The cubic root of 28966139 is about 307.1120593086.

The spelling of 28966139 in words is "twenty-eight million, nine hundred sixty-six thousand, one hundred thirty-nine".