206129849 has 4 divisors (see below), whose sum is σ = 211700964. Its totient is φ = 200558736.

The previous prime is 206129843. The next prime is 206129851. The reversal of 206129849 is 948921602.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 183738025 + 22391824 = 13555^2 + 4732^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-206129849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (206129843) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2785502 + ... + 2785575.

It is an arithmetic number, because the mean of its divisors is an integer number (52925241).

Almost surely, 2^206129849 is an apocalyptic number.

It is an amenable number.

206129849 is a deficient number, since it is larger than the sum of its proper divisors (5571115).

206129849 is an equidigital number, since it uses as much as digits as its factorization.

206129849 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5571114.

The product of its (nonzero) digits is 62208, while the sum is 41.

The square root of 206129849 is about 14357.2228860598. Note that the first 3 decimals coincide. The cubic root of 206129849 is about 590.7181229910.

The spelling of 206129849 in words is "two hundred six million, one hundred twenty-nine thousand, eight hundred forty-nine".