257849840 has 40 divisors (see below), whose sum is σ = 600296400. Its totient is φ = 103003136.

The previous prime is 257849831. The next prime is 257849843. The reversal of 257849840 is 48948752.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257849843) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 76511 + ... + 79809.

It is an arithmetic number, because the mean of its divisors is an integer number (15007410).

Almost surely, 2^257849840 is an apocalyptic number.

257849840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

257849840 is an abundant number, since it is smaller than the sum of its proper divisors (342446560).

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

257849840 is a wasteful number, since it uses less digits than its factorization.

257849840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4289 (or 4283 counting only the distinct ones).

The product of its (nonzero) digits is 645120, while the sum is 47.

The square root of 257849840 is about 16057.7034472555. The cubic root of 257849840 is about 636.4861465061.

The spelling of 257849840 in words is "two hundred fifty-seven million, eight hundred forty-nine thousand, eight hundred forty".