163998641 has 2 divisors, whose sum is σ = 163998642. Its totient is φ = 163998640.

The previous prime is 163998629. The next prime is 163998673. The reversal of 163998641 is 146899361.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 91680625 + 72318016 = 9575^2 + 8504^2 .

It is a cyclic number.

It is not a de Polignac number, because 163998641 - 2¹⁸ = 163736497 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (163998041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 81999320 + 81999321.

It is an arithmetic number, because the mean of its divisors is an integer number (81999321).

Almost surely, 2^163998641 is an apocalyptic number.

It is an amenable number.

163998641 is a deficient number, since it is larger than the sum of its proper divisors (1).

163998641 is an equidigital number, since it uses as much as digits as its factorization.

163998641 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 279936, while the sum is 47.

The square root of 163998641 is about 12806.1954147202. The cubic root of 163998641 is about 547.3688555319.

The spelling of 163998641 in words is "one hundred sixty-three million, nine hundred ninety-eight thousand, six hundred forty-one".