28784661 has 8 divisors (see below), whose sum is σ = 40048320. Its totient is φ = 18355392.

The previous prime is 28784629. The next prime is 28784663. The reversal of 28784661 is 16648782.

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

It is not a de Polignac number, because 28784661 - 2⁵ = 28784629 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28784663) by changing a digit.

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 in 7 ways as a sum of consecutive naturals, for example, 208516 + ... + 208653.

It is an arithmetic number, because the mean of its divisors is an integer number (5006040).

Almost surely, 2^28784661 is an apocalyptic number.

It is an amenable number.

28784661 is a deficient number, since it is larger than the sum of its proper divisors (11263659).

28784661 is a wasteful number, since it uses less digits than its factorization.

28784661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 417195.

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

The square root of 28784661 is about 5365.1338287129. The cubic root of 28784661 is about 306.4693446805.

It can be divided in two parts, 287 and 84661, that added together give a palindrome (84948).

The spelling of 28784661 in words is "twenty-eight million, seven hundred eighty-four thousand, six hundred sixty-one".