28840947 has 8 divisors (see below), whose sum is σ = 38623440. Its totient is φ = 19142880.

The previous prime is 28840937. The next prime is 28840949. The reversal of 28840947 is 74904882.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28840947 - 2⁶ = 28840883 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 28840899 and 28840908.

It is not an unprimeable number, because it can be changed into a prime (28840949) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20304 + ... + 21677.

It is an arithmetic number, because the mean of its divisors is an integer number (4827930).

Almost surely, 2^28840947 is an apocalyptic number.

28840947 is a deficient number, since it is larger than the sum of its proper divisors (9782493).

28840947 is a wasteful number, since it uses less digits than its factorization.

28840947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42213.

The product of its (nonzero) digits is 129024, while the sum is 42.

The square root of 28840947 is about 5370.3768024227. The cubic root of 28840947 is about 306.6689730188.

The spelling of 28840947 in words is "twenty-eight million, eight hundred forty thousand, nine hundred forty-seven".