853840 has 40 divisors (see below), whose sum is σ = 2140488. Its totient is φ = 314880.

The previous prime is 853837. The next prime is 853843. The reversal of 853840 is 48358.

853840 = 34³ + 35³ + ... + 46³.

It is an interprime number because it is at equal distance from previous prime (853837) and next prime (853843).

It can be written as a sum of positive squares in 4 ways, for example, as 64 + 853776 = 8^2 + 924^2 .

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

It is a Smith number, since the sum of its digits (28) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 853799 and 853808.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (853843) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 630 + ... + 1450.

2⁸⁵³⁸⁴⁰ is an apocalyptic number.

853840 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 853840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1070244).

853840 is an abundant number, since it is smaller than the sum of its proper divisors (1286648).

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

853840 is a wasteful number, since it uses less digits than its factorization.

853840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 847 (or 841 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 28.

The square root of 853840 is about 924.0346313856. The cubic root of 853840 is about 94.8692568980.

The spelling of 853840 in words is "eight hundred fifty-three thousand, eight hundred forty".