206838138 has 64 divisors (see below), whose sum is σ = 464550912. Its totient is φ = 60963840.

The previous prime is 206838119. The next prime is 206838143. The reversal of 206838138 is 831838602.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a junction number, because it is equal to n+sod(n) for n = 206838096 and 206838105.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 272856 + ... + 273612.

It is an arithmetic number, because the mean of its divisors is an integer number (7258608).

Almost surely, 2^206838138 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 206838138, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (232275456).

206838138 is an abundant number, since it is smaller than the sum of its proper divisors (257712774).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

206838138 is a wasteful number, since it uses less digits than its factorization.

206838138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 919.

The product of its (nonzero) digits is 55296, while the sum is 39.

The square root of 206838138 is about 14381.8683765358. The cubic root of 206838138 is about 591.3939443058.

The spelling of 206838138 in words is "two hundred six million, eight hundred thirty-eight thousand, one hundred thirty-eight".