63978161 has 6 divisors (see below), whose sum is σ = 69278310. Its totient is φ = 59056608.

The previous prime is 63978151. The next prime is 63978179. The reversal of 63978161 is 16187936.

63978161 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 2825761 + 61152400 = 1681^2 + 7820^2 .

It is not a de Polignac number, because 63978161 - 2⁶ = 63978097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (63978121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 189116 + ... + 189453.

It is an arithmetic number, because the mean of its divisors is an integer number (11546385).

Almost surely, 2^63978161 is an apocalyptic number.

It is an amenable number.

63978161 is a deficient number, since it is larger than the sum of its proper divisors (5300149).

63978161 is a wasteful number, since it uses less digits than its factorization.

63978161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 378595 (or 378582 counting only the distinct ones).

The product of its digits is 54432, while the sum is 41.

The square root of 63978161 is about 7998.6349460392. The cubic root of 63978161 is about 399.9544969072.

The spelling of 63978161 in words is "sixty-three million, nine hundred seventy-eight thousand, one hundred sixty-one".