28657238 has 4 divisors (see below), whose sum is σ = 42985860. Its totient is φ = 14328618.

The previous prime is 28657201. The next prime is 28657243. The reversal of 28657238 is 83275682.

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

It is a junction number, because it is equal to n+sod(n) for n = 28657195 and 28657204.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7164308 + ... + 7164311.

It is an arithmetic number, because the mean of its divisors is an integer number (10746465).

Almost surely, 2^28657238 is an apocalyptic number.

28657238 is a deficient number, since it is larger than the sum of its proper divisors (14328622).

28657238 is a wasteful number, since it uses less digits than its factorization.

28657238 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14328621.

The product of its digits is 161280, while the sum is 41.

The square root of 28657238 is about 5353.2455576033. The cubic root of 28657238 is about 306.0164529009.

The spelling of 28657238 in words is "twenty-eight million, six hundred fifty-seven thousand, two hundred thirty-eight".