838138209 has 16 divisors (see below), whose sum is σ = 1126432320. Its totient is φ = 554319360.

The previous prime is 838138183. The next prime is 838138211. The reversal of 838138209 is 902831838.

It is not a de Polignac number, because 838138209 - 2⁹ = 838137697 is a prime.

It is not an unprimeable number, because it can be changed into a prime (838138219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 211357 + ... + 215285.

It is an arithmetic number, because the mean of its divisors is an integer number (70402020).

Almost surely, 2^838138209 is an apocalyptic number.

It is an amenable number.

838138209 is a deficient number, since it is larger than the sum of its proper divisors (288294111).

838138209 is a wasteful number, since it uses less digits than its factorization.

838138209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4480.

The product of its (nonzero) digits is 82944, while the sum is 42.

The square root of 838138209 is about 28950.6167291821. The cubic root of 838138209 is about 942.8411883336.

The spelling of 838138209 in words is "eight hundred thirty-eight million, one hundred thirty-eight thousand, two hundred nine".