255689940 has 144 divisors (see below), whose sum is σ = 807065280. Its totient is φ = 60403200.

The previous prime is 255689939. The next prime is 255689971. The reversal of 255689940 is 49986552.

It is a self number, because there is not a number n which added to its sum of digits gives 255689940.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 297231 + ... + 298089.

It is an arithmetic number, because the mean of its divisors is an integer number (5604620).

Almost surely, 2^255689940 is an apocalyptic number.

255689940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 255689940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (403532640).

255689940 is an abundant number, since it is smaller than the sum of its proper divisors (551375340).

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

255689940 is a wasteful number, since it uses less digits than its factorization.

255689940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 934 (or 921 counting only the distinct ones).

The product of its (nonzero) digits is 777600, while the sum is 48.

The square root of 255689940 is about 15990.3076893473. The cubic root of 255689940 is about 634.7039684890.

The spelling of 255689940 in words is "two hundred fifty-five million, six hundred eighty-nine thousand, nine hundred forty".