123721428240 has 480 divisors, whose sum is σ = 440915529600. Its totient is φ = 32232038400.

The previous prime is 123721428239. The next prime is 123721428269. The reversal of 123721428240 is 42824127321.

123721428240 is a `hidden beast` number, since 1 + 2 + 372 + 1 + 4 + 282 + 4 + 0 = 666.

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 = 123721428195 and 123721428204.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 308532040 + ... + 308532440.

It is an arithmetic number, because the mean of its divisors is an integer number (918574020).

Almost surely, 2^123721428240 is an apocalyptic number.

123721428240 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 123721428240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (220457764800).

123721428240 is an abundant number, since it is smaller than the sum of its proper divisors (317194101360).

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

123721428240 is a wasteful number, since it uses less digits than its factorization.

123721428240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 757 (or 739 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 36.

The spelling of 123721428240 in words is "one hundred twenty-three billion, seven hundred twenty-one million, four hundred twenty-eight thousand, two hundred forty".