209666501485056 has 4480 divisors, whose sum is σ = 870546887147520. Its totient is φ = 48759924326400.

The previous prime is 209666501485033. The next prime is 209666501485057. The reversal of 209666501485056 is 650584105666902.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a junction number, because it is equal to n+sod(n) for n = 209666501484984 and 209666501485002.

It is not an unprimeable number, because it can be changed into a prime (209666501485057) by changing a digit.

It is a polite number, since it can be written in 447 ways as a sum of consecutive naturals, for example, 1650917334465 + ... + 1650917334591.

Almost surely, 2^{209666501485056} 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 209666501485056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (435273443573760).

209666501485056 is an abundant number, since it is smaller than the sum of its proper divisors (660880385662464).

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

209666501485056 is a wasteful number, since it uses less digits than its factorization.

209666501485056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 338 (or 307 counting only the distinct ones).

The product of its (nonzero) digits is 93312000, while the sum is 63.

The spelling of 209666501485056 in words is "two hundred nine trillion, six hundred sixty-six billion, five hundred one million, four hundred eighty-five thousand, fifty-six".