161560511565 has 16 divisors (see below), whose sum is σ = 258631990848. Its totient is φ = 86120548736.

The previous prime is 161560511467. The next prime is 161560511569. The reversal of 161560511565 is 565115065161.

It is a cyclic number.

It is not a de Polignac number, because 161560511565 - 2¹⁰ = 161560510541 is a prime.

It is a super-2 number, since 2×161560511565² (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 (161560511569) 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, 2786439 + ... + 2843828.

It is an arithmetic number, because the mean of its divisors is an integer number (16164499428).

Almost surely, 2^161560511565 is an apocalyptic number.

161560511565 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

161560511565 is a deficient number, since it is larger than the sum of its proper divisors (97071479283).

161560511565 is a wasteful number, since it uses less digits than its factorization.

161560511565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5632188.

The product of its (nonzero) digits is 135000, while the sum is 42.

The spelling of 161560511565 in words is "one hundred sixty-one billion, five hundred sixty million, five hundred eleven thousand, five hundred sixty-five".