172138618 has 8 divisors (see below), whose sum is σ = 258334848. Its totient is φ = 86027004.

The previous prime is 172138609. The next prime is 172138619. The reversal of 172138618 is 816831271.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (172138619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15796 + ... + 24367.

It is an arithmetic number, because the mean of its divisors is an integer number (32291856).

Almost surely, 2^172138618 is an apocalyptic number.

172138618 is a deficient number, since it is larger than the sum of its proper divisors (86196230).

172138618 is a wasteful number, since it uses less digits than its factorization.

172138618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42308.

The product of its digits is 16128, while the sum is 37.

The square root of 172138618 is about 13120.1607459665. The cubic root of 172138618 is about 556.2791349803.

Adding to 172138618 its reverse (816831271), we get a palindrome (988969889).

The spelling of 172138618 in words is "one hundred seventy-two million, one hundred thirty-eight thousand, six hundred eighteen".