855440 has 60 divisors (see below), whose sum is σ = 2169876. Its totient is φ = 313344.

The previous prime is 855431. The next prime is 855461. The reversal of 855440 is 44558.

It can be written as a sum of positive squares in 6 ways, for example, as 163216 + 692224 = 404^2 + 832^2 .

It is a nialpdrome in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 23102 + ... + 23138.

2⁸⁵⁵⁴⁴⁰ is an apocalyptic number.

855440 is a gapful number since it is divisible by the number (80) 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 855440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1084938).

855440 is an abundant number, since it is smaller than the sum of its proper divisors (1314436).

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

855440 is a wasteful number, since it uses less digits than its factorization.

855440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84 (or 61 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 26.

The square root of 855440 is about 924.8999945940. The cubic root of 855440 is about 94.9284780232.

Adding to 855440 its reverse (44558), we get a palindrome (899998).

It can be divided in two parts, 85 and 5440, that multiplied together give a square (462400 = 680²).

The spelling of 855440 in words is "eight hundred fifty-five thousand, four hundred forty".