209806052013 has 14 divisors (see below), whose sum is σ = 314565179214. Its totient is φ = 139870700856.

The previous prime is 209806051981. The next prime is 209806052017. The reversal of 209806052013 is 310250608902.

209806052013 is a `hidden beast` number, since 20 + 9 + 8 + 0 + 605 + 20 + 1 + 3 = 666.

209806052013 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 172912093929 + 36893958084 = 415827^2 + 192078^2 .

It is not a de Polignac number, because 209806052013 - 2⁵ = 209806051981 is a prime.

It is a super-2 number, since 2×209806052013² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209806052017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 143899170 + ... + 143900627.

Almost surely, 2^209806052013 is an apocalyptic number.

It is an amenable number.

209806052013 is a deficient number, since it is larger than the sum of its proper divisors (104759127201).

209806052013 is an frugal number, since it uses more digits than its factorization.

209806052013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 287799815 (or 287799800 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The spelling of 209806052013 in words is "two hundred nine billion, eight hundred six million, fifty-two thousand, thirteen".