161543517 has 16 divisors (see below), whose sum is σ = 221958912. Its totient is φ = 104431680.

The previous prime is 161543497. The next prime is 161543519. The reversal of 161543517 is 715345161.

It is not a de Polignac number, because 161543517 - 2²⁰ = 160494941 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161543519) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32892 + ... + 37482.

It is an arithmetic number, because the mean of its divisors is an integer number (13872432).

Almost surely, 2^161543517 is an apocalyptic number.

It is an amenable number.

161543517 is a deficient number, since it is larger than the sum of its proper divisors (60415395).

161543517 is a wasteful number, since it uses less digits than its factorization.

161543517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4948.

The product of its digits is 12600, while the sum is 33.

The square root of 161543517 is about 12709.9770652822. The cubic root of 161543517 is about 544.6236685979.

Adding to 161543517 its reverse (715345161), we get a palindrome (876888678).

The spelling of 161543517 in words is "one hundred sixty-one million, five hundred forty-three thousand, five hundred seventeen".