209128312960 has 128 divisors (see below), whose sum is σ = 585304755840. Its totient is φ = 69952266240.

The previous prime is 209128312907. The next prime is 209128312963. The reversal of 209128312960 is 69213821902.

It is a tau number, because it is divible by the number of its divisors (128).

It is not an unprimeable number, because it can be changed into a prime (209128312963) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 385594 + ... + 752953.

It is an arithmetic number, because the mean of its divisors is an integer number (4572693405).

Almost surely, 2^209128312960 is an apocalyptic number.

209128312960 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

209128312960 is an abundant number, since it is smaller than the sum of its proper divisors (376176442880).

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

209128312960 is a wasteful number, since it uses less digits than its factorization.

209128312960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1138614 (or 1138602 counting only the distinct ones).

The product of its (nonzero) digits is 93312, while the sum is 43.

The spelling of 209128312960 in words is "two hundred nine billion, one hundred twenty-eight million, three hundred twelve thousand, nine hundred sixty".