209966562589730 has 16 divisors (see below), whose sum is σ = 385070752524024. Its totient is φ = 82401971733120.

The previous prime is 209966562589681. The next prime is 209966562589739. The reversal of 209966562589730 is 37985265669902.

It is a Cunningham number, because it is equal to 14490223²+1.

It can be written as a sum of positive squares in 4 ways, for example, as 209966562589729 + 1 = 14490223^2 + 1^2 .

It is not an unprimeable number, because it can be changed into a prime (209966562589739) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 198081662291 + ... + 198081663350.

Almost surely, 2^{209966562589730} is an apocalyptic number.

209966562589730 is a deficient number, since it is larger than the sum of its proper divisors (175104189934294).

209966562589730 is a wasteful number, since it uses less digits than its factorization.

209966562589730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 396163325701.

The product of its (nonzero) digits is 2645395200, while the sum is 77.

The spelling of 209966562589730 in words is "two hundred nine trillion, nine hundred sixty-six billion, five hundred sixty-two million, five hundred eighty-nine thousand, seven hundred thirty".