256661501771200 has 168 divisors, whose sum is σ = 659319037264800. Its totient is φ = 98215041576960.

The previous prime is 256661501771153. The next prime is 256661501771201. The reversal of 256661501771200 is 2177105166652.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256661501771201) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 20316244 + ... + 30431443.

Almost surely, 2^{256661501771200} is an apocalyptic number.

256661501771200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256661501771200 is an abundant number, since it is smaller than the sum of its proper divisors (402657535493600).

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

256661501771200 is a wasteful number, since it uses less digits than its factorization.

256661501771200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50747847 (or 50747832 counting only the distinct ones).

The product of its (nonzero) digits is 1058400, while the sum is 49.

The spelling of 256661501771200 in words is "two hundred fifty-six trillion, six hundred sixty-one billion, five hundred one million, seven hundred seventy-one thousand, two hundred".