123138225 has 180 divisors, whose sum is σ = 284790924. Its totient is φ = 52254720.

The previous prime is 123138179. The next prime is 123138233. The reversal of 123138225 is 522831321.

It can be written as a sum of positive squares in 6 ways, for example, as 194481 + 122943744 = 441^2 + 11088^2 .

It is not a de Polignac number, because 123138225 - 2⁸ = 123137969 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 179 ways as a sum of consecutive naturals, for example, 1686789 + ... + 1686861.

Almost surely, 2^123138225 is an apocalyptic number.

123138225 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

123138225 is an abundant number, since it is smaller than the sum of its proper divisors (161652699).

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

123138225 is a wasteful number, since it uses less digits than its factorization.

123138225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126 (or 105 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

The square root of 123138225 is about 11096.7664208994. The cubic root of 123138225 is about 497.5052060430.

Adding to 123138225 its reverse (522831321), we get a palindrome (645969546).

The spelling of 123138225 in words is "one hundred twenty-three million, one hundred thirty-eight thousand, two hundred twenty-five".