Cookie Consent by FreePrivacyPolicy.com
Search a number
7440 = 243531
BaseRepresentation
bin1110100010000
3101012120
41310100
5214230
654240
730456
oct16420
911176
107440
115654
124380
133504
1429d6
152310
hex1d10

7440 has 40 divisors (see below), whose sum is σ = 23808. Its totient is φ = 1920.

The previous prime is 7433. The next prime is 7451. The reversal of 7440 is 447.

7440 is an esthetic number in base 11, because in such base its adjacent digits differ by 1.

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

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a nialpdrome in base 10.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 225 + ... + 255.

27440 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 7440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11904).

7440 is an abundant number, since it is smaller than the sum of its proper divisors (16368).

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

7440 is a wasteful number, since it uses less digits than its factorization.

7440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47 (or 41 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 15.

The square root of 7440 is about 86.2554346114. The cubic root of 7440 is about 19.5220001534.

7440 divided by its sum of digits (15) gives a triangular number (496 = T31).

Adding to 7440 its reverse (447), we get a palindrome (7887).

The spelling of 7440 in words is "seven thousand, four hundred forty", and thus it is an iban number.