161518663 has 2 divisors, whose sum is σ = 161518664. Its totient is φ = 161518662.

The previous prime is 161518657. The next prime is 161518703. The reversal of 161518663 is 366815161.

It is a weak prime.

It is an emirp because it is prime and its reverse (366815161) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 161518663 - 2⁵ = 161518631 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161513663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80759331 + 80759332.

It is an arithmetic number, because the mean of its divisors is an integer number (80759332).

Almost surely, 2^161518663 is an apocalyptic number.

161518663 is a deficient number, since it is larger than the sum of its proper divisors (1).

161518663 is an equidigital number, since it uses as much as digits as its factorization.

161518663 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25920, while the sum is 37.

The square root of 161518663 is about 12708.9992918404. Note that the first 3 decimals coincide. The cubic root of 161518663 is about 544.5957364527.

The spelling of 161518663 in words is "one hundred sixty-one million, five hundred eighteen thousand, six hundred sixty-three".