209309218772 has 48 divisors (see below), whose sum is σ = 380375318400. Its totient is φ = 100658920320.

The previous prime is 209309218771. The next prime is 209309218823. The reversal of 209309218772 is 277812903902.

It is a self number, because there is not a number n which added to its sum of digits gives 209309218772.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209309218771) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44884913 + ... + 44889575.

It is an arithmetic number, because the mean of its divisors is an integer number (7924485800).

Almost surely, 2^209309218772 is an apocalyptic number.

It is an amenable number.

209309218772 is a deficient number, since it is larger than the sum of its proper divisors (171066099628).

209309218772 is a wasteful number, since it uses less digits than its factorization.

209309218772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6096 (or 6094 counting only the distinct ones).

The product of its (nonzero) digits is 762048, while the sum is 50.

The spelling of 209309218772 in words is "two hundred nine billion, three hundred nine million, two hundred eighteen thousand, seven hundred seventy-two".