257780 has 12 divisors (see below), whose sum is σ = 541380. Its totient is φ = 103104.

The previous prime is 257731. The next prime is 257783. The reversal of 257780 is 87752.

It can be written as a sum of positive squares in 2 ways, for example, as 131044 + 126736 = 362^2 + 356^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6425 + ... + 6464.

It is an arithmetic number, because the mean of its divisors is an integer number (45115).

2²⁵⁷⁷⁸⁰ is an apocalyptic number.

257780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

257780 is an abundant number, since it is smaller than the sum of its proper divisors (283600).

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

257780 is a wasteful number, since it uses less digits than its factorization.

257780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12898 (or 12896 counting only the distinct ones).

The product of its (nonzero) digits is 3920, while the sum is 29.

The square root of 257780 is about 507.7203954934. The cubic root of 257780 is about 63.6428676098.

The spelling of 257780 in words is "two hundred fifty-seven thousand, seven hundred eighty".