209720145600000 has 4800 divisors, whose sum is σ = 984011869209600. Its totient is φ = 43438602240000.

The previous prime is 209720145599947. The next prime is 209720145600013. The reversal of 209720145600000 is 6541027902.

209720145600000 is a `hidden beast` number, since 2 + 0 + 9 + 7 + 2 + 0 + 1 + 45 + 600 + 0 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (4800).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 479 ways as a sum of consecutive naturals, for example, 9118267199989 + ... + 9118267200011.

It is an arithmetic number, because the mean of its divisors is an integer number (205002472752).

Almost surely, 2^{209720145600000} is an apocalyptic number.

209720145600000 is a gapful number since it is divisible by the number (20) 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 209720145600000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (492005934604800).

209720145600000 is an abundant number, since it is smaller than the sum of its proper divisors (774291723609600).

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

209720145600000 is an frugal number, since it uses more digits than its factorization.

209720145600000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150 (or 59 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

Adding to 209720145600000 its reverse (6541027902), we get a palindrome (209726686627902).

The spelling of 209720145600000 in words is "two hundred nine trillion, seven hundred twenty billion, one hundred forty-five million, six hundred thousand".