256443100020 has 36 divisors (see below), whose sum is σ = 777877403940. Its totient is φ = 68384826624.

The previous prime is 256443099917. The next prime is 256443100049. The reversal of 256443100020 is 20001344652.

256443100020 is a `hidden beast` number, since 2 + 5 + 644 + 3 + 10 + 0 + 0 + 2 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 95581142244 + 160861957776 = 309162^2 + 401076^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 712341765 + ... + 712342124.

It is an arithmetic number, because the mean of its divisors is an integer number (21607705665).

Almost surely, 2^256443100020 is an apocalyptic number.

256443100020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256443100020 is an abundant number, since it is smaller than the sum of its proper divisors (521434303920).

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

256443100020 is a wasteful number, since it uses less digits than its factorization.

256443100020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1424683904 (or 1424683899 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

Adding to 256443100020 its reverse (20001344652), we get a palindrome (276444444672).

The spelling of 256443100020 in words is "two hundred fifty-six billion, four hundred forty-three million, one hundred thousand, twenty".