Search a number
-
+
84640 = 255232
BaseRepresentation
bin10100101010100000
311022002211
4110222200
510202030
61451504
7501523
oct245240
9138084
1084640
1158656
1240b94
132c6aa
1422bba
151a12a
hex14aa0

84640 has 36 divisors (see below), whose sum is σ = 209034. Its totient is φ = 32384.

The previous prime is 84631. The next prime is 84649. The reversal of 84640 is 4648.

84640 = T16 + T17 + ... + T79.

It is an interprime number because it is at equal distance from previous prime (84631) and next prime (84649).

It can be written as a sum of positive squares in only one way, i.e., 76176 + 8464 = 276^2 + 92^2 .

It is not an unprimeable number, because it can be changed into a prime (84649) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3669 + ... + 3691.

284640 is an apocalyptic number.

84640 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 84640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104517).

84640 is an abundant number, since it is smaller than the sum of its proper divisors (124394).

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

84640 is a wasteful number, since it uses less digits than its factorization.

84640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61 (or 30 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 84640 is about 290.9295447355. The cubic root of 84640 is about 43.9061359930.

The spelling of 84640 in words is "eighty-four thousand, six hundred forty".

Divisors: 1 2 4 5 8 10 16 20 23 32 40 46 80 92 115 160 184 230 368 460 529 736 920 1058 1840 2116 2645 3680 4232 5290 8464 10580 16928 21160 42320 84640