63821660 has 48 divisors (see below), whose sum is σ = 154237440. Its totient is φ = 21729600.

The previous prime is 63821623. The next prime is 63821669. The reversal of 63821660 is 6612836.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63821669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19631 + ... + 22649.

It is an arithmetic number, because the mean of its divisors is an integer number (3213280).

Almost surely, 2^63821660 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 63821660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (77118720).

63821660 is an abundant number, since it is smaller than the sum of its proper divisors (90415780).

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

63821660 is a wasteful number, since it uses less digits than its factorization.

63821660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3186 (or 3184 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 63821660 is about 7988.8459742318. The cubic root of 63821660 is about 399.6281126901.

The spelling of 63821660 in words is "sixty-three million, eight hundred twenty-one thousand, six hundred sixty".