208049821 has 4 divisors (see below), whose sum is σ = 237771232. Its totient is φ = 178328412.

The previous prime is 208049819. The next prime is 208049851. The reversal of 208049821 is 128940802.

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.

It is a cyclic number.

It is not a de Polignac number, because 208049821 - 2¹ = 208049819 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 (208049851) 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, 14860695 + ... + 14860708.

It is an arithmetic number, because the mean of its divisors is an integer number (59442808).

Almost surely, 2^208049821 is an apocalyptic number.

It is an amenable number.

208049821 is a deficient number, since it is larger than the sum of its proper divisors (29721411).

208049821 is an equidigital number, since it uses as much as digits as its factorization.

208049821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29721410.

The product of its (nonzero) digits is 9216, while the sum is 34.

The square root of 208049821 is about 14423.9322308447. The cubic root of 208049821 is about 592.5465158398.

It can be divided in two parts, 20804 and 9821, that added together give a square (30625 = 175²).

The spelling of 208049821 in words is "two hundred eight million, forty-nine thousand, eight hundred twenty-one".