161586506411 has 18 divisors (see below), whose sum is σ = 186071352012. Its totient is φ = 139143596040.

The previous prime is 161586506407. The next prime is 161586506429. The reversal of 161586506411 is 114605685161.

It is not a de Polignac number, because 161586506411 - 2² = 161586506407 is a prime.

It is a super-2 number, since 2×161586506411² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161586506461) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 25327820 + ... + 25334198.

It is an arithmetic number, because the mean of its divisors is an integer number (10337297334).

Almost surely, 2^161586506411 is an apocalyptic number.

161586506411 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

161586506411 is a deficient number, since it is larger than the sum of its proper divisors (24484845601).

161586506411 is an frugal number, since it uses more digits than its factorization.

161586506411 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12807 (or 6409 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 44.

Multiplying 161586506411 by its sum of digits (44), we get a square (7109806282084 = 2666422²).

The spelling of 161586506411 in words is "one hundred sixty-one billion, five hundred eighty-six million, five hundred six thousand, four hundred eleven".