161966172 has 12 divisors (see below), whose sum is σ = 377921096. Its totient is φ = 53988720.

The previous prime is 161966171. The next prime is 161966209. The reversal of 161966172 is 271669161.

161966172 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (12).

It is a hoax number, since the sum of its digits (39) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 161966172.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161966171) 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, 6748579 + ... + 6748602.

Almost surely, 2^161966172 is an apocalyptic number.

161966172 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

161966172 is an abundant number, since it is smaller than the sum of its proper divisors (215954924).

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

161966172 is a wasteful number, since it uses less digits than its factorization.

161966172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13497188 (or 13497186 counting only the distinct ones).

The product of its digits is 27216, while the sum is 39.

The square root of 161966172 is about 12726.5931026336. The cubic root of 161966172 is about 545.0982310382.

The spelling of 161966172 in words is "one hundred sixty-one million, nine hundred sixty-six thousand, one hundred seventy-two".