63685440 has 448 divisors, whose sum is σ = 279928320. Its totient is φ = 13436928.

The previous prime is 63685429. The next prime is 63685441. The reversal of 63685440 is 4458636.

It is a tau number, because it is divible by the number of its divisors (448).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 63685395 and 63685404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63685441) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4898874 + ... + 4898886.

It is an arithmetic number, because the mean of its divisors is an integer number (624840).

Almost surely, 2^63685440 is an apocalyptic number.

63685440 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 63685440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (139964160).

63685440 is an abundant number, since it is smaller than the sum of its proper divisors (216242880).

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

63685440 is an equidigital number, since it uses as much as digits as its factorization.

63685440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58 (or 30 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

The square root of 63685440 is about 7980.3157832256. The cubic root of 63685440 is about 399.3435900709.

The spelling of 63685440 in words is "sixty-three million, six hundred eighty-five thousand, four hundred forty".