123938640 has 240 divisors, whose sum is σ = 497021760. Its totient is φ = 28304640.

The previous prime is 123938623. The next prime is 123938669. The reversal of 123938640 is 46839321.

123938640 is a `hidden beast` number, since 1 + 2 + 3 + 9 + 3 + 8 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 123938595 and 123938604.

It is a congruent number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 105255 + ... + 106425.

It is an arithmetic number, because the mean of its divisors is an integer number (2070924).

Almost surely, 2^123938640 is an apocalyptic number.

123938640 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 123938640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (248510880).

123938640 is an abundant number, since it is smaller than the sum of its proper divisors (373083120).

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

123938640 is a wasteful number, since it uses less digits than its factorization.

123938640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1207 (or 1188 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The square root of 123938640 is about 11132.7732394045. The cubic root of 123938640 is about 498.5808290520.

The spelling of 123938640 in words is "one hundred twenty-three million, nine hundred thirty-eight thousand, six hundred forty".