1808117893 has 2 divisors, whose sum is σ = 1808117894. Its totient is φ = 1808117892.

The previous prime is 1808117827. The next prime is 1808117911. The reversal of 1808117893 is 3987118081.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1647791649 + 160326244 = 40593^2 + 12662^2 .

It is an emirp because it is prime and its reverse (3987118081) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1808117893 - 2¹³ = 1808109701 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1808117393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 904058946 + 904058947.

It is an arithmetic number, because the mean of its divisors is an integer number (904058947).

Almost surely, 2^1808117893 is an apocalyptic number.

It is an amenable number.

1808117893 is a deficient number, since it is larger than the sum of its proper divisors (1).

1808117893 is an equidigital number, since it uses as much as digits as its factorization.

1808117893 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96768, while the sum is 46.

The square root of 1808117893 is about 42521.9695334071. The cubic root of 1808117893 is about 1218.2663481821.

The spelling of 1808117893 in words is "one billion, eight hundred eight million, one hundred seventeen thousand, eight hundred ninety-three".