163689649 has 2 divisors, whose sum is σ = 163689650. Its totient is φ = 163689648.

The previous prime is 163689629. The next prime is 163689661. The reversal of 163689649 is 946986361.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 145371249 + 18318400 = 12057^2 + 4280^2 .

It is an emirp because it is prime and its reverse (946986361) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 163689649 - 2⁷ = 163689521 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 163689596 and 163689605.

It is not a weakly prime, because it can be changed into another prime (163689619) 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, 81844824 + 81844825.

It is an arithmetic number, because the mean of its divisors is an integer number (81844825).

Almost surely, 2^163689649 is an apocalyptic number.

It is an amenable number.

163689649 is a deficient number, since it is larger than the sum of its proper divisors (1).

163689649 is an equidigital number, since it uses as much as digits as its factorization.

163689649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1679616, while the sum is 52.

The square root of 163689649 is about 12794.1255660557. The cubic root of 163689649 is about 547.0248711156.

The spelling of 163689649 in words is "one hundred sixty-three million, six hundred eighty-nine thousand, six hundred forty-nine".