161688166517 has 16 divisors (see below), whose sum is σ = 172843173888. Its totient is φ = 150992054640.

The previous prime is 161688166499. The next prime is 161688166547. The reversal of 161688166517 is 715661886161.

161688166517 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 161688166517 - 2¹² = 161688162421 is a prime.

It is a super-2 number, since 2×161688166517² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161688166547) 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, 620063 + ... + 841340.

It is an arithmetic number, because the mean of its divisors is an integer number (10802698368).

Almost surely, 2^161688166517 is an apocalyptic number.

It is an amenable number.

161688166517 is a deficient number, since it is larger than the sum of its proper divisors (11155007371).

161688166517 is a wasteful number, since it uses less digits than its factorization.

161688166517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1461560.

The product of its digits is 2903040, while the sum is 56.

The spelling of 161688166517 in words is "one hundred sixty-one billion, six hundred eighty-eight million, one hundred sixty-six thousand, five hundred seventeen".