18186335989 has 2 divisors, whose sum is σ = 18186335990. Its totient is φ = 18186335988.

The previous prime is 18186335987. The next prime is 18186336013. The reversal of 18186335989 is 98953368181.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11489696100 + 6696639889 = 107190^2 + 81833^2 .

It is a cyclic number.

It is not a de Polignac number, because 18186335989 - 2¹ = 18186335987 is a prime.

Together with 18186335987, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18186335987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9093167994 + 9093167995.

It is an arithmetic number, because the mean of its divisors is an integer number (9093167995).

Almost surely, 2^18186335989 is an apocalyptic number.

It is an amenable number.

18186335989 is a deficient number, since it is larger than the sum of its proper divisors (1).

18186335989 is an equidigital number, since it uses as much as digits as its factorization.

18186335989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11197440, while the sum is 61.

The spelling of 18186335989 in words is "eighteen billion, one hundred eighty-six million, three hundred thirty-five thousand, nine hundred eighty-nine".