161938009569 has 16 divisors (see below), whose sum is σ = 247640849280. Its totient is φ = 92206692480.

The previous prime is 161938009567. The next prime is 161938009577. The reversal of 161938009569 is 965900839161.

161938009569 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 161938009569 - 2¹ = 161938009567 is a prime.

It is a super-2 number, since 2×161938009569² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (161938009567) 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, 13715334 + ... + 13727135.

It is an arithmetic number, because the mean of its divisors is an integer number (15477553080).

Almost surely, 2^161938009569 is an apocalyptic number.

It is an amenable number.

161938009569 is a deficient number, since it is larger than the sum of its proper divisors (85702839711).

161938009569 is a wasteful number, since it uses less digits than its factorization.

161938009569 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27442760.

The product of its (nonzero) digits is 3149280, while the sum is 57.

The spelling of 161938009569 in words is "one hundred sixty-one billion, nine hundred thirty-eight million, nine thousand, five hundred sixty-nine".