63521647 has 4 divisors (see below), whose sum is σ = 72596176. Its totient is φ = 54447120.

The previous prime is 63521599. The next prime is 63521663. The reversal of 63521647 is 74612536.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 63521647 - 2⁷ = 63521519 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63521747) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4537254 + ... + 4537267.

It is an arithmetic number, because the mean of its divisors is an integer number (18149044).

Almost surely, 2^63521647 is an apocalyptic number.

63521647 is a deficient number, since it is larger than the sum of its proper divisors (9074529).

63521647 is an equidigital number, since it uses as much as digits as its factorization.

63521647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9074528.

The product of its digits is 30240, while the sum is 34.

The square root of 63521647 is about 7970.0468630994. The cubic root of 63521647 is about 399.0009380154. Note that the first 3 decimals are identical.

The spelling of 63521647 in words is "sixty-three million, five hundred twenty-one thousand, six hundred forty-seven".