257781216 has 192 divisors, whose sum is σ = 864331776. Its totient is φ = 65318400.

The previous prime is 257781211. The next prime is 257781299. The reversal of 257781216 is 612187752.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257781211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 317451 + ... + 318261.

It is an arithmetic number, because the mean of its divisors is an integer number (4501728).

Almost surely, 2^257781216 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 257781216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (432165888).

257781216 is an abundant number, since it is smaller than the sum of its proper divisors (606550560).

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

257781216 is a wasteful number, since it uses less digits than its factorization.

257781216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 885 (or 877 counting only the distinct ones).

The product of its digits is 47040, while the sum is 39.

The square root of 257781216 is about 16055.5665113381. The cubic root of 257781216 is about 636.4296768172.

The spelling of 257781216 in words is "two hundred fifty-seven million, seven hundred eighty-one thousand, two hundred sixteen".