257761840 has 40 divisors (see below), whose sum is σ = 684911520. Its totient is φ = 88375296.

The previous prime is 257761813. The next prime is 257761849. The reversal of 257761840 is 48167752.

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

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 257761793 and 257761802.

It is not an unprimeable number, because it can be changed into a prime (257761849) 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 7 ways as a sum of consecutive naturals, for example, 229585 + ... + 230704.

It is an arithmetic number, because the mean of its divisors is an integer number (17122788).

Almost surely, 2^257761840 is an apocalyptic number.

257761840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

257761840 is an abundant number, since it is smaller than the sum of its proper divisors (427149680).

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

257761840 is a wasteful number, since it uses less digits than its factorization.

257761840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 460309 (or 460303 counting only the distinct ones).

The product of its (nonzero) digits is 94080, while the sum is 40.

The square root of 257761840 is about 16054.9630955664. The cubic root of 257761840 is about 636.4137307751.

The spelling of 257761840 in words is "two hundred fifty-seven million, seven hundred sixty-one thousand, eight hundred forty".