Search a number
BaseRepresentation
bin1001110100001101000
3121100012121
41032201220
540243030
610521024
72506504
oct1164150
9540177
10321640
111aa720
12136174
13b3527
1485304
156547a
hex4e868

321640 has 64 divisors (see below), whose sum is σ = 855360. Its totient is φ = 107520.

The previous prime is 321631. The next prime is 321647. The reversal of 321640 is 46123.

Adding to 321640 its reverse (46123), we get a palindrome (367763).

It can be divided in two parts, 321 and 640, that added together give a square (961 = 312).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (321647) by changing a digit.

321640 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 15 ways as a sum of consecutive naturals, for example, 7459 + ... + 7501.

It is an arithmetic number, because the mean of its divisors is an integer number (13365).

2321640 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 321640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (427680).

321640 is an abundant number, since it is smaller than the sum of its proper divisors (533720).

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

321640 is a wasteful number, since it uses less digits than its factorization.

321640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82 (or 78 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 321640 is about 567.1331413346. The cubic root of 321640 is about 68.5156871739.

The spelling of 321640 in words is "three hundred twenty-one thousand, six hundred forty".