123984640 has 72 divisors (see below), whose sum is σ = 319869648. Its totient is φ = 45772800.

The previous prime is 123984629. The next prime is 123984643. The reversal of 123984640 is 46489321.

It is a self number, because there is not a number n which added to its sum of digits gives 123984640.

It is not an unprimeable number, because it can be changed into a prime (123984643) 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 7 ways as a sum of consecutive naturals, for example, 12915 + ... + 20365.

It is an arithmetic number, because the mean of its divisors is an integer number (4442634).

Almost surely, 2^123984640 is an apocalyptic number.

123984640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 123984640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (159934824).

123984640 is an abundant number, since it is smaller than the sum of its proper divisors (195885008).

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

123984640 is an equidigital number, since it uses as much as digits as its factorization.

123984640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7485 (or 7471 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 37.

The square root of 123984640 is about 11134.8390199410. The cubic root of 123984640 is about 498.6425044136.

The spelling of 123984640 in words is "one hundred twenty-three million, nine hundred eighty-four thousand, six hundred forty".