905840 has 60 divisors (see below), whose sum is σ = 2314584. Its totient is φ = 329472.

The previous prime is 905833. The next prime is 905843. The reversal of 905840 is 48509.

905840 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 2×905840² = 1641092211200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (26).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (905843) by changing a digit.

905840 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13487 + ... + 13553.

2⁹⁰⁵⁸⁴⁰ 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 905840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1157292).

905840 is an abundant number, since it is smaller than the sum of its proper divisors (1408744).

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

905840 is a wasteful number, since it uses less digits than its factorization.

905840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106 (or 87 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 905840 is about 951.7562713216. The cubic root of 905840 is about 96.7573201645.

The spelling of 905840 in words is "nine hundred five thousand, eight hundred forty".