63521660 has 24 divisors (see below), whose sum is σ = 133902720. Its totient is φ = 25312064.

The previous prime is 63521599. The next prime is 63521663. The reversal of 63521660 is 6612536.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63521663) 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, 524 + ... + 11283.

It is an arithmetic number, because the mean of its divisors is an integer number (5579280).

Almost surely, 2^63521660 is an apocalyptic number.

It is an amenable number.

63521660 is an abundant number, since it is smaller than the sum of its proper divisors (70381060).

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

63521660 is a wasteful number, since it uses less digits than its factorization.

63521660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12085 (or 12083 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 29.

The square root of 63521660 is about 7970.0476786529. The cubic root of 63521660 is about 399.0009652345. Note that the first 3 decimals are identical.

The spelling of 63521660 in words is "sixty-three million, five hundred twenty-one thousand, six hundred sixty".