257871817728 has 616 divisors, whose sum is σ = 898886172960. Its totient is φ = 72380252160.

The previous prime is 257871817681. The next prime is 257871817747. The reversal of 257871817728 is 827718178752.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 318753388 + ... + 318754196.

Almost surely, 2^257871817728 is an apocalyptic number.

257871817728 is a gapful number since it is divisible by the number (28) 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 257871817728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (449443086480).

257871817728 is an abundant number, since it is smaller than the sum of its proper divisors (641014355232).

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

257871817728 is an frugal number, since it uses more digits than its factorization.

257871817728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 915 (or 882 counting only the distinct ones).

The product of its digits is 24586240, while the sum is 63.

The spelling of 257871817728 in words is "two hundred fifty-seven billion, eight hundred seventy-one million, eight hundred seventeen thousand, seven hundred twenty-eight".