163891763641 has 2 divisors, whose sum is σ = 163891763642. Its totient is φ = 163891763640.

The previous prime is 163891763639. The next prime is 163891763653. The reversal of 163891763641 is 146367198361.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 89087325625 + 74804438016 = 298475^2 + 273504^2 .

It is an emirp because it is prime and its reverse (146367198361) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 163891763641 - 2¹ = 163891763639 is a prime.

Together with 163891763639, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (163891763141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 81945881820 + 81945881821.

It is an arithmetic number, because the mean of its divisors is an integer number (81945881821).

Almost surely, 2^163891763641 is an apocalyptic number.

It is an amenable number.

163891763641 is a deficient number, since it is larger than the sum of its proper divisors (1).

163891763641 is an equidigital number, since it uses as much as digits as its factorization.

163891763641 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3919104, while the sum is 55.

The spelling of 163891763641 in words is "one hundred sixty-three billion, eight hundred ninety-one million, seven hundred sixty-three thousand, six hundred forty-one".