256033917440 has 320 divisors, whose sum is σ = 712181631744. Its totient is φ = 86467411968.

The previous prime is 256033917427. The next prime is 256033917449. The reversal of 256033917440 is 44719330652.

It is a tau number, because it is divible by the number of its divisors (320).

It is a junction number, because it is equal to n+sod(n) for n = 256033917391 and 256033917400.

It is not an unprimeable number, because it can be changed into a prime (256033917449) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 459665642 + ... + 459666198.

Almost surely, 2^256033917440 is an apocalyptic number.

256033917440 is a gapful number since it is divisible by the number (20) 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 256033917440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (356090815872).

256033917440 is an abundant number, since it is smaller than the sum of its proper divisors (456147714304).

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

256033917440 is a wasteful number, since it uses less digits than its factorization.

256033917440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 927 (or 911 counting only the distinct ones).

The product of its (nonzero) digits is 544320, while the sum is 44.

The spelling of 256033917440 in words is "two hundred fifty-six billion, thirty-three million, nine hundred seventeen thousand, four hundred forty".