256641053520 has 80 divisors (see below), whose sum is σ = 842386530240. Its totient is φ = 64411871232.

The previous prime is 256641053507. The next prime is 256641053563. The reversal of 256641053520 is 25350146652.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31447030 + ... + 31455189.

It is an arithmetic number, because the mean of its divisors is an integer number (10529831628).

Almost surely, 2^256641053520 is an apocalyptic number.

256641053520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256641053520 is an abundant number, since it is smaller than the sum of its proper divisors (585745476720).

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

256641053520 is a wasteful number, since it uses less digits than its factorization.

256641053520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62902252 (or 62902246 counting only the distinct ones).

The product of its (nonzero) digits is 216000, while the sum is 39.

The spelling of 256641053520 in words is "two hundred fifty-six billion, six hundred forty-one million, fifty-three thousand, five hundred twenty".