209061101824 has 135 divisors (see below), whose sum is σ = 454379327185. Its totient is φ = 95982141440.

The previous prime is 209061101749. The next prime is 209061101839. The reversal of 209061101824 is 428101160902.

It is a happy number.

The square root of 209061101824 is 457232.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 7 ways, for example, as 208593158400 + 467943424 = 456720^2 + 21632^2 .

It is a super-2 number, since 2×209061101824² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 209061101824.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 5099051244 + ... + 5099051284.

Almost surely, 2^209061101824 is an apocalyptic number.

209061101824 is the 457232-nd square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 209061101824

209061101824 is an abundant number, since it is smaller than the sum of its proper divisors (245318225361).

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

209061101824 is an frugal number, since it uses more digits than its factorization.

209061101824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214 (or 60 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 34.

The spelling of 209061101824 in words is "two hundred nine billion, sixty-one million, one hundred one thousand, eight hundred twenty-four".