206131687 has 2 divisors, whose sum is σ = 206131688. Its totient is φ = 206131686.

The previous prime is 206131649. The next prime is 206131721. The reversal of 206131687 is 786131602.

206131687 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an a-pointer prime, because the next prime (206131721) can be obtained adding 206131687 to its sum of digits (34).

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 206131687 - 2¹⁹ = 205607399 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (206131087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103065843 + 103065844.

It is an arithmetic number, because the mean of its divisors is an integer number (103065844).

Almost surely, 2^206131687 is an apocalyptic number.

206131687 is a deficient number, since it is larger than the sum of its proper divisors (1).

206131687 is an equidigital number, since it uses as much as digits as its factorization.

206131687 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 206131687 is about 14357.2868955106. The cubic root of 206131687 is about 590.7198787398.

The spelling of 206131687 in words is "two hundred six million, one hundred thirty-one thousand, six hundred eighty-seven".