161573442621 has 16 divisors (see below), whose sum is σ = 219045801600. Its totient is φ = 105909693120.

The previous prime is 161573442599. The next prime is 161573442631. The reversal of 161573442621 is 126244375161.

161573442621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 161573442621 - 2⁶ = 161573442557 is a prime.

It is a super-2 number, since 2×161573442621² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161573442631) 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 in 15 ways as a sum of consecutive naturals, for example, 321555 + ... + 653103.

It is an arithmetic number, because the mean of its divisors is an integer number (13690362600).

Almost surely, 2^161573442621 is an apocalyptic number.

It is an amenable number.

161573442621 is a deficient number, since it is larger than the sum of its proper divisors (57472358979).

161573442621 is a wasteful number, since it uses less digits than its factorization.

161573442621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 334276.

The product of its digits is 241920, while the sum is 42.

The spelling of 161573442621 in words is "one hundred sixty-one billion, five hundred seventy-three million, four hundred forty-two thousand, six hundred twenty-one".