28304947 has 16 divisors (see below), whose sum is σ = 31701600. Its totient is φ = 25056000.

The previous prime is 28304933. The next prime is 28304959. The reversal of 28304947 is 74940382.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 28304947 - 2⁷ = 28304819 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28304917) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 80929 + ... + 81277.

It is an arithmetic number, because the mean of its divisors is an integer number (1981350).

Almost surely, 2^28304947 is an apocalyptic number.

28304947 is a deficient number, since it is larger than the sum of its proper divisors (3396653).

28304947 is a wasteful number, since it uses less digits than its factorization.

28304947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 534.

The product of its (nonzero) digits is 48384, while the sum is 37.

The square root of 28304947 is about 5320.2393743139. The cubic root of 28304947 is about 304.7572986372.

It can be divided in two parts, 2830 and 4947, that added together give a palindrome (7777).

The spelling of 28304947 in words is "twenty-eight million, three hundred four thousand, nine hundred forty-seven".