863440 has 40 divisors (see below), whose sum is σ = 2062368. Its totient is φ = 336000.

The previous prime is 863393. The next prime is 863479. The reversal of 863440 is 44368.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3315 + ... + 3565.

2⁸⁶³⁴⁴⁰ is an apocalyptic number.

863440 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 863440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1031184).

863440 is an abundant number, since it is smaller than the sum of its proper divisors (1198928).

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

863440 is a wasteful number, since it uses less digits than its factorization.

863440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 307 (or 301 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 863440 is about 929.2147222252. The cubic root of 863440 is about 95.2234812497.

The spelling of 863440 in words is "eight hundred sixty-three thousand, four hundred forty".