63530721 has 6 divisors (see below), whose sum is σ = 91766610. Its totient is φ = 42353808.

The previous prime is 63530711. The next prime is 63530723. The reversal of 63530721 is 12703536.

It is a happy number.

63530721 is a `hidden beast` number, since 63 + 530 + 72 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 59120721 + 4410000 = 7689^2 + 2100^2 .

It is not a de Polignac number, because 63530721 - 2¹⁴ = 63514337 is a prime.

It is not an unprimeable number, because it can be changed into a prime (63530723) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3529476 + ... + 3529493.

It is an arithmetic number, because the mean of its divisors is an integer number (15294435).

Almost surely, 2^63530721 is an apocalyptic number.

It is an amenable number.

63530721 is a deficient number, since it is larger than the sum of its proper divisors (28235889).

63530721 is a wasteful number, since it uses less digits than its factorization.

63530721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7058975 (or 7058972 counting only the distinct ones).

The product of its (nonzero) digits is 3780, while the sum is 27.

The square root of 63530721 is about 7970.6160991482. The cubic root of 63530721 is about 399.0199360646.

The spelling of 63530721 in words is "sixty-three million, five hundred thirty thousand, seven hundred twenty-one".