428389209 has 8 divisors (see below), whose sum is σ = 634650720. Its totient is φ = 285592788.

The previous prime is 428389207. The next prime is 428389249. The reversal of 428389209 is 902983824.

It is not a de Polignac number, because 428389209 - 2¹ = 428389207 is a prime.

It is not an unprimeable number, because it can be changed into a prime (428389201) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7933107 + ... + 7933160.

It is an arithmetic number, because the mean of its divisors is an integer number (79331340).

Almost surely, 2^428389209 is an apocalyptic number.

It is an amenable number.

428389209 is a deficient number, since it is larger than the sum of its proper divisors (206261511).

428389209 is a wasteful number, since it uses less digits than its factorization.

428389209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15866276 (or 15866270 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 45.

The square root of 428389209 is about 20697.5652915989. The cubic root of 428389209 is about 753.8405717752.

The spelling of 428389209 in words is "four hundred twenty-eight million, three hundred eighty-nine thousand, two hundred nine".