63728591 has 16 divisors (see below), whose sum is σ = 67995648. Its totient is φ = 59637600.

The previous prime is 63728579. The next prime is 63728593. The reversal of 63728591 is 19582736.

It is a cyclic number.

It is not a de Polignac number, because 63728591 - 2¹⁰ = 63727567 is a prime.

It is a super-2 number, since 2×63728591² = 8122666621690562, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63728593) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 126446 + ... + 126948.

It is an arithmetic number, because the mean of its divisors is an integer number (4249728).

Almost surely, 2^63728591 is an apocalyptic number.

63728591 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

63728591 is a deficient number, since it is larger than the sum of its proper divisors (4267057).

63728591 is a wasteful number, since it uses less digits than its factorization.

63728591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 662.

The product of its digits is 90720, while the sum is 41.

The square root of 63728591 is about 7983.0189151724. The cubic root of 63728591 is about 399.4337634018.

The spelling of 63728591 in words is "sixty-three million, seven hundred twenty-eight thousand, five hundred ninety-one".