161563523 has 16 divisors (see below), whose sum is σ = 184896000. Its totient is φ = 139740480.

The previous prime is 161563463. The next prime is 161563541. The reversal of 161563523 is 325365161.

It is not a de Polignac number, because 161563523 - 2¹⁸ = 161301379 is a prime.

It is a super-2 number, since 2×161563523² = 52205543928343058, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 161563523.

It is not an unprimeable number, because it can be changed into a prime (161563543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 48743 + ... + 51951.

It is an arithmetic number, because the mean of its divisors is an integer number (11556000).

Almost surely, 2^161563523 is an apocalyptic number.

161563523 is a deficient number, since it is larger than the sum of its proper divisors (23332477).

161563523 is a wasteful number, since it uses less digits than its factorization.

161563523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3442.

The product of its digits is 16200, while the sum is 32.

The square root of 161563523 is about 12710.7640604332. The cubic root of 161563523 is about 544.6461502416.

The spelling of 161563523 in words is "one hundred sixty-one million, five hundred sixty-three thousand, five hundred twenty-three".