172135123 has 2 divisors, whose sum is σ = 172135124. Its totient is φ = 172135122.

The previous prime is 172135109. The next prime is 172135129. The reversal of 172135123 is 321531271.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (321531271) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 172135123 - 2⁵ = 172135091 is a prime.

It is not a weakly prime, because it can be changed into another prime (172135129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86067561 + 86067562.

It is an arithmetic number, because the mean of its divisors is an integer number (86067562).

Almost surely, 2^172135123 is an apocalyptic number.

172135123 is a deficient number, since it is larger than the sum of its proper divisors (1).

172135123 is an equidigital number, since it uses as much as digits as its factorization.

172135123 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1260, while the sum is 25.

The square root of 172135123 is about 13120.0275533247. The cubic root of 172135123 is about 556.2753701680.

Adding to 172135123 its reverse (321531271), we get a palindrome (493666394).

The spelling of 172135123 in words is "one hundred seventy-two million, one hundred thirty-five thousand, one hundred twenty-three".