209138716072 has 128 divisors (see below), whose sum is σ = 488129846400. Its totient is φ = 82531123200.

The previous prime is 209138716067. The next prime is 209138716097. The reversal of 209138716072 is 270617831902.

209138716072 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×209138716072² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 37551304 + ... + 37556872.

It is an arithmetic number, because the mean of its divisors is an integer number (3813514425).

Almost surely, 2^209138716072 is an apocalyptic number.

209138716072 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 209138716072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (244064923200).

209138716072 is an abundant number, since it is smaller than the sum of its proper divisors (278991130328).

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

209138716072 is a wasteful number, since it uses less digits than its factorization.

209138716072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7547 (or 7543 counting only the distinct ones).

The product of its (nonzero) digits is 254016, while the sum is 46.

The spelling of 209138716072 in words is "two hundred nine billion, one hundred thirty-eight million, seven hundred sixteen thousand, seventy-two".