255805640 has 16 divisors (see below), whose sum is σ = 575562780. Its totient is φ = 102322240.

The previous prime is 255805637. The next prime is 255805663. The reversal of 255805640 is 46508552.

It can be written as a sum of positive squares in 2 ways, for example, as 222188836 + 33616804 = 14906^2 + 5798^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 255805640.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3197531 + ... + 3197610.

Almost surely, 2^255805640 is an apocalyptic number.

255805640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

255805640 is an abundant number, since it is smaller than the sum of its proper divisors (319757140).

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

255805640 is a wasteful number, since it uses less digits than its factorization.

255805640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6395152 (or 6395148 counting only the distinct ones).

The product of its (nonzero) digits is 48000, while the sum is 35.

The square root of 255805640 is about 15993.9250967359. The cubic root of 255805640 is about 634.7996888178.

The spelling of 255805640 in words is "two hundred fifty-five million, eight hundred five thousand, six hundred forty".