9181819091009 has 2 divisors, whose sum is σ = 9181819091010. Its totient is φ = 9181819091008.

The previous prime is 9181819090991. The next prime is 9181819091021. The reversal of 9181819091009 is 9001909181819.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5553186510400 + 3628632580609 = 2356520^2 + 1904897^2 .

It is a cyclic number.

It is not a de Polignac number, because 9181819091009 - 2⁴⁰ = 8082307463233 is a prime.

It is not a weakly prime, because it can be changed into another prime (9181819094009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4590909545504 + 4590909545505.

It is an arithmetic number, because the mean of its divisors is an integer number (4590909545505).

Almost surely, 2^{9181819091009} is an apocalyptic number.

It is an amenable number.

9181819091009 is a deficient number, since it is larger than the sum of its proper divisors (1).

9181819091009 is an equidigital number, since it uses as much as digits as its factorization.

9181819091009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 419904, while the sum is 56.

The spelling of 9181819091009 in words is "nine trillion, one hundred eighty-one billion, eight hundred nineteen million, ninety-one thousand, nine".