161117819 has 12 divisors (see below), whose sum is σ = 168143040. Its totient is φ = 154223280.

The previous prime is 161117809. The next prime is 161117851. The reversal of 161117819 is 918711161.

It is a de Polignac number, because none of the positive numbers 2^k-161117819 is a prime.

It is a super-2 number, since 2×161117819² = 51917903198633522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161117809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 598817 + ... + 599085.

It is an arithmetic number, because the mean of its divisors is an integer number (14011920).

Almost surely, 2^161117819 is an apocalyptic number.

161117819 is a deficient number, since it is larger than the sum of its proper divisors (7025221).

161117819 is an equidigital number, since it uses as much as digits as its factorization.

161117819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 578 (or 439 counting only the distinct ones).

The product of its digits is 3024, while the sum is 35.

The square root of 161117819 is about 12693.2194103781. The cubic root of 161117819 is about 544.1448519885.

The spelling of 161117819 in words is "one hundred sixty-one million, one hundred seventeen thousand, eight hundred nineteen".