209149470 has 96 divisors (see below), whose sum is σ = 579301632. Its totient is φ = 52171776.

The previous prime is 209149441. The next prime is 209149471. The reversal of 209149470 is 74941902.

209149470 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209149471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 340884 + ... + 341496.

It is an arithmetic number, because the mean of its divisors is an integer number (6034392).

Almost surely, 2^209149470 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 209149470, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (289650816).

209149470 is an abundant number, since it is smaller than the sum of its proper divisors (370152162).

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

209149470 is a wasteful number, since it uses less digits than its factorization.

209149470 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 866 (or 863 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 209149470 is about 14462.0008989075. Note that the first 3 decimals coincide. The cubic root of 209149470 is about 593.5886517079.

The spelling of 209149470 in words is "two hundred nine million, one hundred forty-nine thousand, four hundred seventy".