123681538 has 8 divisors (see below), whose sum is σ = 185754060. Its totient is φ = 61763520.

The previous prime is 123681527. The next prime is 123681539. The reversal of 123681538 is 835186321.

It can be written as a sum of positive squares in 2 ways, for example, as 119968209 + 3713329 = 10953^2 + 1927^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 123681497 and 123681506.

It is not an unprimeable number, because it can be changed into a prime (123681539) 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, 36603 + ... + 39838.

Almost surely, 2^123681538 is an apocalyptic number.

123681538 is a deficient number, since it is larger than the sum of its proper divisors (62072522).

123681538 is an equidigital number, since it uses as much as digits as its factorization.

123681538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77252.

The product of its digits is 34560, while the sum is 37.

The square root of 123681538 is about 11121.2201668702. The cubic root of 123681538 is about 498.2358334200.

The spelling of 123681538 in words is "one hundred twenty-three million, six hundred eighty-one thousand, five hundred thirty-eight".