194455813 has 2 divisors, whose sum is σ = 194455814. Its totient is φ = 194455812.

The previous prime is 194455787. The next prime is 194455819. The reversal of 194455813 is 318554491.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 123609924 + 70845889 = 11118^2 + 8417^2 .

It is an emirp because it is prime and its reverse (318554491) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-194455813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (194455819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97227906 + 97227907.

It is an arithmetic number, because the mean of its divisors is an integer number (97227907).

Almost surely, 2^194455813 is an apocalyptic number.

It is an amenable number.

194455813 is a deficient number, since it is larger than the sum of its proper divisors (1).

194455813 is an equidigital number, since it uses as much as digits as its factorization.

194455813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 86400, while the sum is 40.

The square root of 194455813 is about 13944.7414102951. The cubic root of 194455813 is about 579.3490646140.

The spelling of 194455813 in words is "one hundred ninety-four million, four hundred fifty-five thousand, eight hundred thirteen".