123396438240 has 144 divisors (see below), whose sum is σ = 424120460400. Its totient is φ = 32668932096.

The previous prime is 123396438233. The next prime is 123396438281. The reversal of 123396438240 is 42834693321.

123396438240 is a `hidden beast` number, since 12 + 3 + 396 + 4 + 3 + 8 + 240 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 108085 + ... + 508404.

It is an arithmetic number, because the mean of its divisors is an integer number (2945280975).

Almost surely, 2^123396438240 is an apocalyptic number.

123396438240 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 123396438240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (212060230200).

123396438240 is an abundant number, since it is smaller than the sum of its proper divisors (300724022160).

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

123396438240 is a wasteful number, since it uses less digits than its factorization.

123396438240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 616649 (or 616638 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 45.

The spelling of 123396438240 in words is "one hundred twenty-three billion, three hundred ninety-six million, four hundred thirty-eight thousand, two hundred forty".