206757681 has 16 divisors (see below), whose sum is σ = 300953856. Its totient is φ = 125490816.

The previous prime is 206757679. The next prime is 206757697. The reversal of 206757681 is 186757602.

It is not a de Polignac number, because 206757681 - 2¹ = 206757679 is a prime.

It is a super-2 number, since 2×206757681² = 85497477304995522, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (206757641) 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, 33465 + ... + 39158.

It is an arithmetic number, because the mean of its divisors is an integer number (18809616).

Almost surely, 2^206757681 is an apocalyptic number.

It is an amenable number.

206757681 is a deficient number, since it is larger than the sum of its proper divisors (94196175).

206757681 is a wasteful number, since it uses less digits than its factorization.

206757681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72712.

The product of its (nonzero) digits is 141120, while the sum is 42.

The square root of 206757681 is about 14379.0709366078. The cubic root of 206757681 is about 591.3172531728.

The spelling of 206757681 in words is "two hundred six million, seven hundred fifty-seven thousand, six hundred eighty-one".