209728512 has 132 divisors (see below), whose sum is σ = 692311776. Its totient is φ = 59904000.

The previous prime is 209728499. The next prime is 209728529. The reversal of 209728512 is 215827902.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 62887 + ... + 66137.

Almost surely, 2^209728512 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 209728512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (346155888).

209728512 is an abundant number, since it is smaller than the sum of its proper divisors (482583264).

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

209728512 is a wasteful number, since it uses less digits than its factorization.

209728512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3284 (or 3263 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 209728512 is about 14482.0064908147. The cubic root of 209728512 is about 594.1359414062.

The spelling of 209728512 in words is "two hundred nine million, seven hundred twenty-eight thousand, five hundred twelve".