209913072 has 80 divisors (see below), whose sum is σ = 558312480. Its totient is φ = 67931136.

The previous prime is 209913043. The next prime is 209913089. The reversal of 209913072 is 270319902.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 276918 + ... + 277674.

It is an arithmetic number, because the mean of its divisors is an integer number (6978906).

Almost surely, 2^209913072 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 209913072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (279156240).

209913072 is an abundant number, since it is smaller than the sum of its proper divisors (348399408).

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

209913072 is a wasteful number, since it uses less digits than its factorization.

209913072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 930 (or 924 counting only the distinct ones).

The product of its (nonzero) digits is 6804, while the sum is 33.

The square root of 209913072 is about 14488.3771347933. The cubic root of 209913072 is about 594.3101691560.

The spelling of 209913072 in words is "two hundred nine million, nine hundred thirteen thousand, seventy-two".