163503197681 has 2 divisors, whose sum is σ = 163503197682. Its totient is φ = 163503197680.

The previous prime is 163503197651. The next prime is 163503197687. The reversal of 163503197681 is 186791305361.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 103823150656 + 59680047025 = 322216^2 + 244295^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-163503197681 is a prime.

It is a super-2 number, since 2×163503197681² (a number of 23 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (163503197687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 81751598840 + 81751598841.

It is an arithmetic number, because the mean of its divisors is an integer number (81751598841).

Almost surely, 2^163503197681 is an apocalyptic number.

It is an amenable number.

163503197681 is a deficient number, since it is larger than the sum of its proper divisors (1).

163503197681 is an equidigital number, since it uses as much as digits as its factorization.

163503197681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 816480, while the sum is 50.

The spelling of 163503197681 in words is "one hundred sixty-three billion, five hundred three million, one hundred ninety-seven thousand, six hundred eighty-one".