255405440 has 32 divisors (see below), whose sum is σ = 610580160. Its totient is φ = 102161920.

The previous prime is 255405439. The next prime is 255405443. The reversal of 255405440 is 44504552.

It is a tau number, because it is divible by the number of its divisors (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (255405443) 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, 198896 + ... + 200175.

It is an arithmetic number, because the mean of its divisors is an integer number (19080630).

Almost surely, 2^255405440 is an apocalyptic number.

255405440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

255405440 is an abundant number, since it is smaller than the sum of its proper divisors (355174720).

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

255405440 is an equidigital number, since it uses as much as digits as its factorization.

255405440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 399090 (or 399078 counting only the distinct ones).

The product of its (nonzero) digits is 16000, while the sum is 29.

The square root of 255405440 is about 15981.4091994417. The cubic root of 255405440 is about 634.4684745497.

Adding to 255405440 its reverse (44504552), we get a palindrome (299909992).

The spelling of 255405440 in words is "two hundred fifty-five million, four hundred five thousand, four hundred forty".