63440 has 40 divisors (see below), whose sum is σ = 161448. Its totient is φ = 23040.

The previous prime is 63439. The next prime is 63443. The reversal of 63440 is 4436.

It can be written as a sum of positive squares in 4 ways, for example, as 1936 + 61504 = 44^2 + 248^2 .

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63443) 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, 1010 + ... + 1070.

2⁶³⁴⁴⁰ 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 63440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80724).

63440 is an abundant number, since it is smaller than the sum of its proper divisors (98008).

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

63440 is a wasteful number, since it uses less digits than its factorization.

63440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87 (or 81 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 17.

The square root of 63440 is about 251.8729838629. The cubic root of 63440 is about 39.8829913917.

Adding to 63440 its reverse (4436), we get a palindrome (67876).

The spelling of 63440 in words is "sixty-three thousand, four hundred forty".