161531873228 has 24 divisors (see below), whose sum is σ = 318326744064. Its totient is φ = 71055075600.

The previous prime is 161531873161. The next prime is 161531873231. The reversal of 161531873228 is 822378135161.

It is a super-3 number, since 3×161531873228³ (a number of 35 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 59211200 + ... + 59213927.

It is an arithmetic number, because the mean of its divisors is an integer number (13263614336).

Almost surely, 2^161531873228 is an apocalyptic number.

It is an amenable number.

161531873228 is a deficient number, since it is larger than the sum of its proper divisors (156794870836).

161531873228 is a wasteful number, since it uses less digits than its factorization.

161531873228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118425173 (or 118425171 counting only the distinct ones).

The product of its digits is 483840, while the sum is 47.

The spelling of 161531873228 in words is "one hundred sixty-one billion, five hundred thirty-one million, eight hundred seventy-three thousand, two hundred twenty-eight".