209672736345 has 48 divisors (see below), whose sum is σ = 375362741520. Its totient is φ = 108212502528.

The previous prime is 209672736337. The next prime is 209672736379. The reversal of 209672736345 is 543637276902.

209672736345 is a `hidden beast` number, since 20 + 9 + 6 + 7 + 273 + 6 + 345 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 2294505801 + 207378230544 = 47901^2 + 455388^2 .

It is not a de Polignac number, because 209672736345 - 2³ = 209672736337 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 209672736291 and 209672736300.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 428040 + ... + 776249.

It is an arithmetic number, because the mean of its divisors is an integer number (7820057115).

Almost surely, 2^209672736345 is an apocalyptic number.

It is an amenable number.

209672736345 is a deficient number, since it is larger than the sum of its proper divisors (165690005175).

209672736345 is a wasteful number, since it uses less digits than its factorization.

209672736345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1204426 (or 1204423 counting only the distinct ones).

The product of its (nonzero) digits is 11430720, while the sum is 54.

The spelling of 209672736345 in words is "two hundred nine billion, six hundred seventy-two million, seven hundred thirty-six thousand, three hundred forty-five".