172013728 has 12 divisors (see below), whose sum is σ = 338652090. Its totient is φ = 86006848.

The previous prime is 172013713. The next prime is 172013729. The reversal of 172013728 is 827310271.

It can be written as a sum of positive squares in only one way, i.e., 162103824 + 9909904 = 12732^2 + 3148^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 172013728.

It is not an unprimeable number, because it can be changed into a prime (172013729) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2687683 + ... + 2687746.

Almost surely, 2^172013728 is an apocalyptic number.

It is an amenable number.

172013728 is a deficient number, since it is larger than the sum of its proper divisors (166638362).

172013728 is an equidigital number, since it uses as much as digits as its factorization.

172013728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5375439 (or 5375431 counting only the distinct ones).

The product of its (nonzero) digits is 4704, while the sum is 31.

The square root of 172013728 is about 13115.4004132546. The cubic root of 172013728 is about 556.1445718972.

Adding to 172013728 its reverse (827310271), we get a palindrome (999323999).

The spelling of 172013728 in words is "one hundred seventy-two million, thirteen thousand, seven hundred twenty-eight".