28956139 has 4 divisors (see below), whose sum is σ = 29890240. Its totient is φ = 28022040.

The previous prime is 28956131. The next prime is 28956167. The reversal of 28956139 is 93165982.

It is a happy number.

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 28956139 - 2³ = 28956131 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28956095 and 28956104.

It is not an unprimeable number, because it can be changed into a prime (28956131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 467004 + ... + 467065.

It is an arithmetic number, because the mean of its divisors is an integer number (7472560).

Almost surely, 2^28956139 is an apocalyptic number.

28956139 is a deficient number, since it is larger than the sum of its proper divisors (934101).

28956139 is an equidigital number, since it uses as much as digits as its factorization.

28956139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 934100.

The product of its digits is 116640, while the sum is 43.

The square root of 28956139 is about 5381.0908745346. The cubic root of 28956139 is about 307.0767137387.

The spelling of 28956139 in words is "twenty-eight million, nine hundred fifty-six thousand, one hundred thirty-nine".