209769665384 has 8 divisors (see below), whose sum is σ = 393318122610. Its totient is φ = 104884832688.

The previous prime is 209769665383. The next prime is 209769665401. The reversal of 209769665384 is 483566967902.

It can be written as a sum of positive squares in only one way, i.e., 148627212484 + 61142452900 = 385522^2 + 247270^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a self number, because there is not a number n which added to its sum of digits gives 209769665384.

It is not an unprimeable number, because it can be changed into a prime (209769665383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13110604079 + ... + 13110604094.

Almost surely, 2^209769665384 is an apocalyptic number.

It is an amenable number.

209769665384 is a deficient number, since it is larger than the sum of its proper divisors (183548457226).

209769665384 is a wasteful number, since it uses less digits than its factorization.

209769665384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26221208179 (or 26221208175 counting only the distinct ones).

The product of its (nonzero) digits is 117573120, while the sum is 65.

The spelling of 209769665384 in words is "two hundred nine billion, seven hundred sixty-nine million, six hundred sixty-five thousand, three hundred eighty-four".