163540510621 has 2 divisors, whose sum is σ = 163540510622. Its totient is φ = 163540510620.

The previous prime is 163540510547. The next prime is 163540510631. The reversal of 163540510621 is 126015045361.

163540510621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 85972690521 + 77567820100 = 293211^2 + 278510^2 .

It is a cyclic number.

It is not a de Polignac number, because 163540510621 - 2²⁵ = 163506956189 is a prime.

It is a super-2 number, since 2×163540510621² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (163540510631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 81770255310 + 81770255311.

It is an arithmetic number, because the mean of its divisors is an integer number (81770255311).

Almost surely, 2^163540510621 is an apocalyptic number.

It is an amenable number.

163540510621 is a deficient number, since it is larger than the sum of its proper divisors (1).

163540510621 is an equidigital number, since it uses as much as digits as its factorization.

163540510621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21600, while the sum is 34.

Adding to 163540510621 its reverse (126015045361), we get a palindrome (289555555982).

The spelling of 163540510621 in words is "one hundred sixty-three billion, five hundred forty million, five hundred ten thousand, six hundred twenty-one".