208138011 has 4 divisors (see below), whose sum is σ = 277517352. Its totient is φ = 138758672.

The previous prime is 208138003. The next prime is 208138019. The reversal of 208138011 is 110831802.

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

It is an interprime number because it is at equal distance from previous prime (208138003) and next prime (208138019).

It is a cyclic number.

It is not a de Polignac number, because 208138011 - 2³ = 208138003 is a prime.

It is a super-2 number, since 2×208138011² = 86642863246072242, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (208138019) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34689666 + ... + 34689671.

It is an arithmetic number, because the mean of its divisors is an integer number (69379338).

Almost surely, 2^208138011 is an apocalyptic number.

208138011 is a deficient number, since it is larger than the sum of its proper divisors (69379341).

208138011 is an equidigital number, since it uses as much as digits as its factorization.

208138011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69379340.

The product of its (nonzero) digits is 384, while the sum is 24.

The square root of 208138011 is about 14426.9889789935. The cubic root of 208138011 is about 592.6302286336.

Adding to 208138011 its reverse (110831802), we get a palindrome (318969813).

The spelling of 208138011 in words is "two hundred eight million, one hundred thirty-eight thousand, eleven".