161218173 has 8 divisors (see below), whose sum is σ = 226271200. Its totient is φ = 101821968.

The previous prime is 161218159. The next prime is 161218193. The reversal of 161218173 is 371812161.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 161218173 - 2²⁴ = 144440957 is a prime.

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 161218173.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161218153) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1414138 + ... + 1414251.

It is an arithmetic number, because the mean of its divisors is an integer number (28283900).

Almost surely, 2^161218173 is an apocalyptic number.

It is an amenable number.

161218173 is a deficient number, since it is larger than the sum of its proper divisors (65053027).

161218173 is a wasteful number, since it uses less digits than its factorization.

161218173 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2828411.

The product of its digits is 2016, while the sum is 30.

The square root of 161218173 is about 12697.1718504555. The cubic root of 161218173 is about 544.2578040695.

The spelling of 161218173 in words is "one hundred sixty-one million, two hundred eighteen thousand, one hundred seventy-three".