63728643 has 18 divisors (see below), whose sum is σ = 93621892. Its totient is φ = 38531240.

The previous prime is 63728629. The next prime is 63728659. The reversal of 63728643 is 34682736.

It is not a de Polignac number, because 63728643 - 2⁴ = 63728627 is a prime.

It is a super-2 number, since 2×63728643² = 8122679877242898, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (63728683) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 151888 + ... + 152306.

Almost surely, 2^63728643 is an apocalyptic number.

63728643 is a deficient number, since it is larger than the sum of its proper divisors (29893249).

63728643 is an equidigital number, since it uses as much as digits as its factorization.

63728643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 863 (or 433 counting only the distinct ones).

The product of its digits is 145152, while the sum is 39.

The square root of 63728643 is about 7983.0221720850. The cubic root of 63728643 is about 399.4338720425.

The spelling of 63728643 in words is "sixty-three million, seven hundred twenty-eight thousand, six hundred forty-three".