840312 has 48 divisors (see below), whose sum is σ = 2485080. Its totient is φ = 254400.

The previous prime is 840299. The next prime is 840319. The reversal of 840312 is 213048.

It is a happy number.

840312 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×840312² = 1412248514688, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 840312.

It is not an unprimeable number, because it can be changed into a prime (840319) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 262 + ... + 1322.

2⁸⁴⁰³¹² is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 840312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1242540).

840312 is an abundant number, since it is smaller than the sum of its proper divisors (1644768).

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

840312 is a wasteful number, since it uses less digits than its factorization.

840312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1084 (or 1077 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 840312 is about 916.6853331433. The cubic root of 840312 is about 94.3655600692.

Subtracting from 840312 its reverse (213048), we obtain a square (627264 = 792²).

The spelling of 840312 in words is "eight hundred forty thousand, three hundred twelve".