209429028 has 36 divisors (see below), whose sum is σ = 543701340. Its totient is φ = 67922496.

The previous prime is 209429009. The next prime is 209429047. The reversal of 209429028 is 820924902.

209429028 is a `hidden beast` number, since 209 + 429 + 0 + 28 = 666.

209429028 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (209429009) and next prime (209429047).

It can be written as a sum of positive squares in 2 ways, for example, as 105021504 + 104407524 = 10248^2 + 10218^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 209428983 and 209429001.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 77283 + ... + 79946.

It is an arithmetic number, because the mean of its divisors is an integer number (15102815).

Almost surely, 2^209429028 is an apocalyptic number.

It is an amenable number.

209429028 is an abundant number, since it is smaller than the sum of its proper divisors (334272312).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

209429028 is a wasteful number, since it uses less digits than its factorization.

209429028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157276 (or 157271 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 209429028 is about 14471.6629313980. The cubic root of 209429028 is about 593.8530058337.

The spelling of 209429028 in words is "two hundred nine million, four hundred twenty-nine thousand, twenty-eight".