28507937 has 4 divisors (see below), whose sum is σ = 28522260. Its totient is φ = 28493616.

The previous prime is 28507933. The next prime is 28507939. The reversal of 28507937 is 73970582.

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

It can be written as a sum of positive squares in 2 ways, for example, as 15555136 + 12952801 = 3944^2 + 3599^2 .

It is a cyclic number.

It is not a de Polignac number, because 28507937 - 2² = 28507933 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28507894 and 28507903.

It is not an unprimeable number, because it can be changed into a prime (28507931) 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, 3578 + ... + 8355.

It is an arithmetic number, because the mean of its divisors is an integer number (7130565).

Almost surely, 2^28507937 is an apocalyptic number.

It is an amenable number.

28507937 is a deficient number, since it is larger than the sum of its proper divisors (14323).

28507937 is a wasteful number, since it uses less digits than its factorization.

28507937 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14322.

The product of its (nonzero) digits is 105840, while the sum is 41.

The square root of 28507937 is about 5339.2824424261. The cubic root of 28507937 is about 305.4840901638.

The spelling of 28507937 in words is "twenty-eight million, five hundred seven thousand, nine hundred thirty-seven".