256123384128 has 672 divisors, whose sum is σ = 850410288000. Its totient is φ = 76187381760.

The previous prime is 256123384103. The next prime is 256123384177. The reversal of 256123384128 is 821483321652.

256123384128 is a `hidden beast` number, since 2 + 5 + 612 + 3 + 3 + 8 + 4 + 1 + 28 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 6246911788 + ... + 6246911828.

It is an arithmetic number, because the mean of its divisors is an integer number (1265491500).

Almost surely, 2^256123384128 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 256123384128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (425205144000).

256123384128 is an abundant number, since it is smaller than the sum of its proper divisors (594286903872).

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

256123384128 is an frugal number, since it uses more digits than its factorization.

256123384128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134 (or 94 counting only the distinct ones).

The product of its digits is 552960, while the sum is 45.

The spelling of 256123384128 in words is "two hundred fifty-six billion, one hundred twenty-three million, three hundred eighty-four thousand, one hundred twenty-eight".