172991984 has 20 divisors (see below), whose sum is σ = 365642520. Its totient is φ = 78632640.

The previous prime is 172991981. The next prime is 172991999. The reversal of 172991984 is 489199271.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172991981) 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, 491279 + ... + 491630.

It is an arithmetic number, because the mean of its divisors is an integer number (18282126).

Almost surely, 2^172991984 is an apocalyptic number.

It is an amenable number.

172991984 is an abundant number, since it is smaller than the sum of its proper divisors (192650536).

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

172991984 is a wasteful number, since it uses less digits than its factorization.

172991984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 982928 (or 982922 counting only the distinct ones).

The product of its digits is 326592, while the sum is 50.

The square root of 172991984 is about 13152.6417118387. The cubic root of 172991984 is about 557.1968593346.

The spelling of 172991984 in words is "one hundred seventy-two million, nine hundred ninety-one thousand, nine hundred eighty-four".