63728517 has 4 divisors (see below), whose sum is σ = 84971360. Its totient is φ = 42485676.

The previous prime is 63728513. The next prime is 63728531. The reversal of 63728517 is 71582736.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 63728517 - 2² = 63728513 is a prime.

It is a super-2 number, since 2×63728517² = 8122647758038578, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63728513) 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, 10621417 + ... + 10621422.

It is an arithmetic number, because the mean of its divisors is an integer number (21242840).

Almost surely, 2^63728517 is an apocalyptic number.

It is an amenable number.

63728517 is a deficient number, since it is larger than the sum of its proper divisors (21242843).

63728517 is a wasteful number, since it uses less digits than its factorization.

63728517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21242842.

The product of its digits is 70560, while the sum is 39.

The square root of 63728517 is about 7983.0142803330. The cubic root of 63728517 is about 399.4336087977.

The spelling of 63728517 in words is "sixty-three million, seven hundred twenty-eight thousand, five hundred seventeen".