161317084181 has 4 divisors (see below), whose sum is σ = 175982273664. Its totient is φ = 146651894700.

The previous prime is 161317084133. The next prime is 161317084273. The reversal of 161317084181 is 181480713161.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 161317084181 - 2¹⁰ = 161317083157 is a prime.

It is a super-2 number, since 2×161317084181² (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 (161317084111) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7332594725 + ... + 7332594746.

It is an arithmetic number, because the mean of its divisors is an integer number (43995568416).

Almost surely, 2^161317084181 is an apocalyptic number.

161317084181 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

161317084181 is a deficient number, since it is larger than the sum of its proper divisors (14665189483).

161317084181 is a wasteful number, since it uses less digits than its factorization.

161317084181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14665189482.

The product of its (nonzero) digits is 32256, while the sum is 41.

The spelling of 161317084181 in words is "one hundred sixty-one billion, three hundred seventeen million, eighty-four thousand, one hundred eighty-one".