209091484320016 has 135 divisors (see below), whose sum is σ = 432312715726767. Its totient is φ = 97948542504960.

The previous prime is 209091484320013. The next prime is 209091484320023. The reversal of 209091484320016 is 610023484190902.

It is a happy number.

The square root of 209091484320016 is 14459996.

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

It can be written as a sum of positive squares in 4 ways, for example, as 656430521616 + 208435053798400 = 810204^2 + 14437280^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (209091484320011) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 331365268021 + ... + 331365268651.

Almost surely, 2^{209091484320016} is an apocalyptic number.

209091484320016 is the 14459996-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 209091484320016

209091484320016 is an abundant number, since it is smaller than the sum of its proper divisors (223221231406751).

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

209091484320016 is an frugal number, since it uses more digits than its factorization.

209091484320016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1978 (or 987 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 49.

The spelling of 209091484320016 in words is "two hundred nine trillion, ninety-one billion, four hundred eighty-four million, three hundred twenty thousand, sixteen".