209724243984 has 40 divisors (see below), whose sum is σ = 601986257120. Its totient is φ = 69908081184.

The previous prime is 209724243973. The next prime is 209724244003. The reversal of 209724243984 is 489342427902.

209724243984 is a `hidden beast` number, since 2 + 0 + 9 + 7 + 242 + 4 + 398 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 209724243984.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 242735962 + ... + 242736825.

It is an arithmetic number, because the mean of its divisors is an integer number (15049656428).

Almost surely, 2^209724243984 is an apocalyptic number.

209724243984 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

209724243984 is an abundant number, since it is smaller than the sum of its proper divisors (392262013136).

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

209724243984 is a wasteful number, since it uses less digits than its factorization.

209724243984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 485472804 (or 485472792 counting only the distinct ones).

The product of its (nonzero) digits is 6967296, while the sum is 54.

The spelling of 209724243984 in words is "two hundred nine billion, seven hundred twenty-four million, two hundred forty-three thousand, nine hundred eighty-four".