28709371 has 4 divisors (see below), whose sum is σ = 28836072. Its totient is φ = 28582672.

The previous prime is 28709363. The next prime is 28709377. The reversal of 28709371 is 17390782.

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 28709371 - 2³ = 28709363 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 28709371.

It is not an unprimeable number, because it can be changed into a prime (28709377) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 63010 + ... + 63463.

It is an arithmetic number, because the mean of its divisors is an integer number (7209018).

Almost surely, 2^28709371 is an apocalyptic number.

28709371 is a deficient number, since it is larger than the sum of its proper divisors (126701).

28709371 is a wasteful number, since it uses less digits than its factorization.

28709371 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126700.

The product of its (nonzero) digits is 21168, while the sum is 37.

The square root of 28709371 is about 5358.1126341278. The cubic root of 28709371 is about 306.2019079835.

The spelling of 28709371 in words is "twenty-eight million, seven hundred nine thousand, three hundred seventy-one".