209386087145 has 4 divisors (see below), whose sum is σ = 251263304580. Its totient is φ = 167508869712.

The previous prime is 209386087123. The next prime is 209386087147. The reversal of 209386087145 is 541780683902.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 84440804569 + 124945282576 = 290587^2 + 353476^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-209386087145 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (209386087147) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20938608710 + ... + 20938608719.

It is an arithmetic number, because the mean of its divisors is an integer number (62815826145).

It is a 1-persistent number, because it is pandigital, but 2⋅209386087145 = 418772174290 is not.

Almost surely, 2^209386087145 is an apocalyptic number.

It is an amenable number.

209386087145 is a deficient number, since it is larger than the sum of its proper divisors (41877217435).

209386087145 is an equidigital number, since it uses as much as digits as its factorization.

209386087145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41877217434.

The product of its (nonzero) digits is 2903040, while the sum is 53.

The spelling of 209386087145 in words is "two hundred nine billion, three hundred eighty-six million, eighty-seven thousand, one hundred forty-five".