208338821 has 4 divisors (see below), whose sum is σ = 210361632. Its totient is φ = 206316012.

The previous prime is 208338787. The next prime is 208338833. The reversal of 208338821 is 128833802.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 128833802 = 2 ⋅64416901.

It is a cyclic number.

It is not a de Polignac number, because 208338821 - 2¹⁸ = 208076677 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (208335821) 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 3 ways as a sum of consecutive naturals, for example, 1011251 + ... + 1011456.

It is an arithmetic number, because the mean of its divisors is an integer number (52590408).

Almost surely, 2^208338821 is an apocalyptic number.

It is an amenable number.

208338821 is a deficient number, since it is larger than the sum of its proper divisors (2022811).

208338821 is a wasteful number, since it uses less digits than its factorization.

208338821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2022810.

The product of its (nonzero) digits is 18432, while the sum is 35.

The square root of 208338821 is about 14433.9468268385. The cubic root of 208338821 is about 592.8207557813.

It can be divided in two parts, 2083 and 38821, that added together give a palindrome (40904).

The spelling of 208338821 in words is "two hundred eight million, three hundred thirty-eight thousand, eight hundred twenty-one".