63840 has 96 divisors (see below), whose sum is σ = 241920. Its totient is φ = 13824.

The previous prime is 63839. The next prime is 63841. The reversal of 63840 is 4836.

63840 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (63839) and next prime (63841).

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a nialpdrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63841) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3351 + ... + 3369.

It is an arithmetic number, because the mean of its divisors is an integer number (2520).

2⁶³⁸⁴⁰ is an apocalyptic number.

63840 is a gapful number since it is divisible by the number (60) 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 63840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120960).

63840 is an abundant number, since it is smaller than the sum of its proper divisors (178080).

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

63840 is a wasteful number, since it uses less digits than its factorization.

63840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44 (or 36 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 63840 is about 252.6657871577. The cubic root of 63840 is about 39.9666388502.

It can be divided in two parts, 63 and 840, that added together give a triangular number (903 = T₄₂).

The spelling of 63840 in words is "sixty-three thousand, eight hundred forty".