28784029 has 4 divisors (see below), whose sum is σ = 28798876. Its totient is φ = 28769184.

The previous prime is 28784023. The next prime is 28784033. The reversal of 28784029 is 92048782.

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 21483225 + 7300804 = 4635^2 + 2702^2 .

It is a cyclic number.

It is not a de Polignac number, because 28784029 - 2²³ = 20395421 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28783982 and 28784000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28784023) 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, 3984 + ... + 8569.

It is an arithmetic number, because the mean of its divisors is an integer number (7199719).

Almost surely, 2^28784029 is an apocalyptic number.

It is an amenable number.

28784029 is a deficient number, since it is larger than the sum of its proper divisors (14847).

28784029 is a wasteful number, since it uses less digits than its factorization.

28784029 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14846.

The product of its (nonzero) digits is 64512, while the sum is 40.

The square root of 28784029 is about 5365.0749295793. The cubic root of 28784029 is about 306.4671017030.

The spelling of 28784029 in words is "twenty-eight million, seven hundred eighty-four thousand, twenty-nine".