161993272 has 64 divisors (see below), whose sum is σ = 369515520. Its totient is φ = 64992768.

The previous prime is 161993269. The next prime is 161993311. The reversal of 161993272 is 272399161.

161993272 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 250053 + ... + 250699.

It is an arithmetic number, because the mean of its divisors is an integer number (5773680).

Almost surely, 2^161993272 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161993272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (184757760).

161993272 is an abundant number, since it is smaller than the sum of its proper divisors (207522248).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161993272 is a wasteful number, since it uses less digits than its factorization.

161993272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 940 (or 936 counting only the distinct ones).

The product of its digits is 40824, while the sum is 40.

The square root of 161993272 is about 12727.6577578123. The cubic root of 161993272 is about 545.1286310863.

The spelling of 161993272 in words is "one hundred sixty-one million, nine hundred ninety-three thousand, two hundred seventy-two".