209640960000 has 780 divisors, whose sum is σ = 787056742472. Its totient is φ = 55738368000.

The previous prime is 209640959963. The next prime is 209640960037. The reversal of 209640960000 is 69046902.

209640960000 is a `hidden beast` number, since 2 + 0 + 9 + 6 + 40 + 9 + 600 + 0 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (209640959963) and next prime (209640960037).

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

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 622079832 + ... + 622080168.

Almost surely, 2^209640960000 is an apocalyptic number.

209640960000 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 209640960000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (393528371236).

209640960000 is an abundant number, since it is smaller than the sum of its proper divisors (577415782472).

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

209640960000 is an frugal number, since it uses more digits than its factorization.

209640960000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 396 (or 347 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 36.

The spelling of 209640960000 in words is "two hundred nine billion, six hundred forty million, nine hundred sixty thousand".