123638856 has 64 divisors (see below), whose sum is σ = 338644800. Its totient is φ = 37305600.

The previous prime is 123638839. The next prime is 123638857. The reversal of 123638856 is 658836321.

It is not an unprimeable number, because it can be changed into a prime (123638857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 70146 + ... + 71886.

It is an arithmetic number, because the mean of its divisors is an integer number (5291325).

Almost surely, 2^123638856 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 123638856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (169322400).

123638856 is an abundant number, since it is smaller than the sum of its proper divisors (215005944).

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

123638856 is a wasteful number, since it uses less digits than its factorization.

123638856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2030 (or 2026 counting only the distinct ones).

The product of its digits is 207360, while the sum is 42.

The square root of 123638856 is about 11119.3010571708. The cubic root of 123638856 is about 498.1785137669.

The spelling of 123638856 in words is "one hundred twenty-three million, six hundred thirty-eight thousand, eight hundred fifty-six".