172012128 has 24 divisors (see below), whose sum is σ = 451532088. Its totient is φ = 57337344.

The previous prime is 172012123. The next prime is 172012153. The reversal of 172012128 is 821210271.

It is a tau number, because it is divible by the number of its divisors (24).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a junction number, because it is equal to n+sod(n) for n = 172012098 and 172012107.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172012123) 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, 895801 + ... + 895992.

It is an arithmetic number, because the mean of its divisors is an integer number (18813837).

Almost surely, 2^172012128 is an apocalyptic number.

It is an amenable number.

172012128 is an abundant number, since it is smaller than the sum of its proper divisors (279519960).

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

172012128 is a wasteful number, since it uses less digits than its factorization.

172012128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1791806 (or 1791798 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 24.

The square root of 172012128 is about 13115.3394161188. The cubic root of 172012128 is about 556.1428475502.

Adding to 172012128 its reverse (821210271), we get a palindrome (993222399).

The spelling of 172012128 in words is "one hundred seventy-two million, twelve thousand, one hundred twenty-eight".