172128240 has 200 divisors, whose sum is σ = 606041568. Its totient is φ = 45273600.

The previous prime is 172128223. The next prime is 172128263. The reversal of 172128240 is 42821271.

172128240 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-3 number, since 3×172128240³ (a number of 26 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 654349 + ... + 654611.

Almost surely, 2^172128240 is an apocalyptic number.

172128240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 172128240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (303020784).

172128240 is an abundant number, since it is smaller than the sum of its proper divisors (433913328).

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

172128240 is a wasteful number, since it uses less digits than its factorization.

172128240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 389 (or 374 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 27.

The square root of 172128240 is about 13119.7652418022. The cubic root of 172128240 is about 556.2679556549.

It can be divided in two parts, 17212 and 8240, that added together give a palindrome (25452).

The spelling of 172128240 in words is "one hundred seventy-two million, one hundred twenty-eight thousand, two hundred forty".