206056747981 has 16 divisors (see below), whose sum is σ = 253933868160. Its totient is φ = 163243192320.

The previous prime is 206056747849. The next prime is 206056747997. The reversal of 206056747981 is 189747650602.

It is a cyclic number.

It is not a de Polignac number, because 206056747981 - 2¹¹ = 206056745933 is a prime.

It is a super-2 number, since 2×206056747981² (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 (206056747081) 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, 18888436 + ... + 18899341.

It is an arithmetic number, because the mean of its divisors is an integer number (15870866760).

Almost surely, 2^206056747981 is an apocalyptic number.

It is an amenable number.

206056747981 is a deficient number, since it is larger than the sum of its proper divisors (47877120179).

206056747981 is a wasteful number, since it uses less digits than its factorization.

206056747981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37787844.

The product of its (nonzero) digits is 5080320, while the sum is 55.

The spelling of 206056747981 in words is "two hundred six billion, fifty-six million, seven hundred forty-seven thousand, nine hundred eighty-one".