209008728 has 64 divisors (see below), whose sum is σ = 605836800. Its totient is φ = 66638880.

The previous prime is 209008717. The next prime is 209008763. The reversal of 209008728 is 827800902.

It is a super-3 number, since 3×209008728³ (a number of 26 digits) contains 333 as substring.

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 = 209008692 and 209008701.

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 16068 + ... + 26003.

It is an arithmetic number, because the mean of its divisors is an integer number (9466200).

Almost surely, 2^209008728 is an apocalyptic number.

It is an amenable number.

209008728 is an abundant number, since it is smaller than the sum of its proper divisors (396828072).

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

209008728 is a wasteful number, since it uses less digits than its factorization.

209008728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42109 (or 42099 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 209008728 is about 14457.1341558415. The cubic root of 209008728 is about 593.4554748617.

The spelling of 209008728 in words is "two hundred nine million, eight thousand, seven hundred twenty-eight".