172239428 has 12 divisors (see below), whose sum is σ = 302748432. Its totient is φ = 85739880.

The previous prime is 172239421. The next prime is 172239437. The reversal of 172239428 is 824932271.

It is a junction number, because it is equal to n+sod(n) for n = 172239391 and 172239400.

It is not an unprimeable number, because it can be changed into a prime (172239421) 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, 93938 + ... + 95753.

It is an arithmetic number, because the mean of its divisors is an integer number (25229036).

Almost surely, 2^172239428 is an apocalyptic number.

It is an amenable number.

172239428 is a deficient number, since it is larger than the sum of its proper divisors (130509004).

172239428 is a wasteful number, since it uses less digits than its factorization.

172239428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 189922 (or 189920 counting only the distinct ones).

The product of its digits is 48384, while the sum is 38.

The square root of 172239428 is about 13124.0019811032. The cubic root of 172239428 is about 556.3877055356.

The spelling of 172239428 in words is "one hundred seventy-two million, two hundred thirty-nine thousand, four hundred twenty-eight".