63644660 has 24 divisors (see below), whose sum is σ = 134511720. Its totient is φ = 25294464.

The previous prime is 63644641. The next prime is 63644663. The reversal of 63644660 is 6644636.

It can be written as a sum of positive squares in 4 ways, for example, as 7873636 + 55771024 = 2806^2 + 7468^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 63644660.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63644663) 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, 6995 + ... + 13274.

It is an arithmetic number, because the mean of its divisors is an integer number (5604655).

Almost surely, 2^63644660 is an apocalyptic number.

It is an amenable number.

63644660 is an abundant number, since it is smaller than the sum of its proper divisors (70867060).

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

63644660 is a wasteful number, since it uses less digits than its factorization.

63644660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20435 (or 20433 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 35.

The square root of 63644660 is about 7977.7603373378. The cubic root of 63644660 is about 399.2583340122.

The spelling of 63644660 in words is "sixty-three million, six hundred forty-four thousand, six hundred sixty".