257742 has 40 divisors (see below), whose sum is σ = 606936. Its totient is φ = 81648.

The previous prime is 257731. The next prime is 257783. The reversal of 257742 is 247752.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

257742 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 19 ways as a sum of consecutive naturals, for example, 5973 + ... + 6015.

2²⁵⁷⁷⁴² is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 257742, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (303468).

257742 is an abundant number, since it is smaller than the sum of its proper divisors (349194).

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

257742 is a wasteful number, since it uses less digits than its factorization.

257742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94 (or 85 counting only the distinct ones).

The product of its digits is 3920, while the sum is 27.

The square root of 257742 is about 507.6829719421. The cubic root of 257742 is about 63.6397402043.

It can be divided in two parts, 257 and 742, that added together give a palindrome (999).

The spelling of 257742 in words is "two hundred fifty-seven thousand, seven hundred forty-two".