208257517823 has 2 divisors, whose sum is σ = 208257517824. Its totient is φ = 208257517822.

The previous prime is 208257517789. The next prime is 208257517883. The reversal of 208257517823 is 328715752802.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 208257517823 - 2⁶ = 208257517759 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (208257517883) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104128758911 + 104128758912.

It is an arithmetic number, because the mean of its divisors is an integer number (104128758912).

Almost surely, 2^208257517823 is an apocalyptic number.

208257517823 is a deficient number, since it is larger than the sum of its proper divisors (1).

208257517823 is an equidigital number, since it uses as much as digits as its factorization.

208257517823 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1881600, while the sum is 50.

The spelling of 208257517823 in words is "two hundred eight billion, two hundred fifty-seven million, five hundred seventeen thousand, eight hundred twenty-three".