206931808869 has 16 divisors (see below), whose sum is σ = 276323450880. Its totient is φ = 137747478960.

The previous prime is 206931808861. The next prime is 206931808879. The reversal of 206931808869 is 968808139602.

It is a happy number.

It is not a de Polignac number, because 206931808869 - 2³ = 206931808861 is a prime.

It is a super-2 number, since 2×206931808869² (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 (206931808861) 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, 7417104 + ... + 7444950.

It is an arithmetic number, because the mean of its divisors is an integer number (17270215680).

Almost surely, 2^206931808869 is an apocalyptic number.

It is an amenable number.

206931808869 is a deficient number, since it is larger than the sum of its proper divisors (69391642011).

206931808869 is a wasteful number, since it uses less digits than its factorization.

206931808869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31480.

The product of its (nonzero) digits is 8957952, while the sum is 60.

The spelling of 206931808869 in words is "two hundred six billion, nine hundred thirty-one million, eight hundred eight thousand, eight hundred sixty-nine".