28409133 has 4 divisors (see below), whose sum is σ = 37878848. Its totient is φ = 18939420.

The previous prime is 28409131. The next prime is 28409153. The reversal of 28409133 is 33190482.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 28409133 - 2¹ = 28409131 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28409133.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28409131) 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, 4734853 + ... + 4734858.

It is an arithmetic number, because the mean of its divisors is an integer number (9469712).

Almost surely, 2^28409133 is an apocalyptic number.

It is an amenable number.

28409133 is a deficient number, since it is larger than the sum of its proper divisors (9469715).

28409133 is an equidigital number, since it uses as much as digits as its factorization.

28409133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9469714.

The product of its (nonzero) digits is 5184, while the sum is 30.

The square root of 28409133 is about 5330.0218573661. The cubic root of 28409133 is about 305.1307618113.

The spelling of 28409133 in words is "twenty-eight million, four hundred nine thousand, one hundred thirty-three".