28909247 has 8 divisors (see below), whose sum is σ = 30027600. Its totient is φ = 27808704.

The previous prime is 28909219. The next prime is 28909249. The reversal of 28909247 is 74290982.

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

It is a cyclic number.

It is not a de Polignac number, because 28909247 - 2⁸ = 28908991 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28909249) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1097 + ... + 7682.

It is an arithmetic number, because the mean of its divisors is an integer number (3753450).

Almost surely, 2^28909247 is an apocalyptic number.

28909247 is a deficient number, since it is larger than the sum of its proper divisors (1118353).

28909247 is an equidigital number, since it uses as much as digits as its factorization.

28909247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8905.

The product of its (nonzero) digits is 72576, while the sum is 41.

The square root of 28909247 is about 5376.7320000164. The cubic root of 28909247 is about 306.9108626544.

The spelling of 28909247 in words is "twenty-eight million, nine hundred nine thousand, two hundred forty-seven".