256516021263000 has 128 divisors (see below), whose sum is σ = 800499556059840. Its totient is φ = 68389779200000.

The previous prime is 256516021262993. The next prime is 256516021263041. The reversal of 256516021263000 is 362120615652.

It is a self number, because there is not a number n which added to its sum of digits gives 256516021263000.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5107150 + ... + 23218850.

Almost surely, 2^{256516021263000} is an apocalyptic number.

256516021263000 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 256516021263000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (400249778029920).

256516021263000 is an abundant number, since it is smaller than the sum of its proper divisors (543983534796840).

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

256516021263000 is a wasteful number, since it uses less digits than its factorization.

256516021263000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18116446 (or 18116432 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 39.

Adding to 256516021263000 its reverse (362120615652), we get a palindrome (256878141878652).

The spelling of 256516021263000 in words is "two hundred fifty-six trillion, five hundred sixteen billion, twenty-one million, two hundred sixty-three thousand".