208320811 has 4 divisors (see below), whose sum is σ = 210164472. Its totient is φ = 206477152.

The previous prime is 208320797. The next prime is 208320817. The reversal of 208320811 is 118023802.

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

It is a cyclic number.

It is not a de Polignac number, because 208320811 - 2¹¹ = 208318763 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (208320817) 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, 921661 + ... + 921886.

It is an arithmetic number, because the mean of its divisors is an integer number (52541118).

Almost surely, 2^208320811 is an apocalyptic number.

208320811 is a deficient number, since it is larger than the sum of its proper divisors (1843661).

208320811 is a wasteful number, since it uses less digits than its factorization.

208320811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1843660.

The product of its (nonzero) digits is 768, while the sum is 25.

The square root of 208320811 is about 14433.3229368708. The cubic root of 208320811 is about 592.8036730161.

The spelling of 208320811 in words is "two hundred eight million, three hundred twenty thousand, eight hundred eleven".