208612813 has 2 divisors, whose sum is σ = 208612814. Its totient is φ = 208612812.

The previous prime is 208612793. The next prime is 208612841. The reversal of 208612813 is 318216802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 203290564 + 5322249 = 14258^2 + 2307^2 .

It is a cyclic number.

It is not a de Polignac number, because 208612813 - 2¹³ = 208604621 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (208612843) 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 as a sum of consecutive naturals, namely, 104306406 + 104306407.

It is an arithmetic number, because the mean of its divisors is an integer number (104306407).

Almost surely, 2^208612813 is an apocalyptic number.

It is an amenable number.

208612813 is a deficient number, since it is larger than the sum of its proper divisors (1).

208612813 is an equidigital number, since it uses as much as digits as its factorization.

208612813 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4608, while the sum is 31.

The square root of 208612813 is about 14443.4349446383. The cubic root of 208612813 is about 593.0805201260.

The spelling of 208612813 in words is "two hundred eight million, six hundred twelve thousand, eight hundred thirteen".