63998472865 has 8 divisors (see below), whose sum is σ = 77196086568. Its totient is φ = 50933498880.

The previous prime is 63998472817. The next prime is 63998472893. The reversal of 63998472865 is 56827489936.

It can be written as a sum of positive squares in 4 ways, for example, as 3250026081 + 60748446784 = 57009^2 + 246472^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 63998472865 - 2⁹ = 63998472353 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 63998472865.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33158866 + ... + 33160795.

It is an arithmetic number, because the mean of its divisors is an integer number (9649510821).

Almost surely, 2^63998472865 is an apocalyptic number.

It is an amenable number.

63998472865 is a deficient number, since it is larger than the sum of its proper divisors (13197613703).

63998472865 is a wasteful number, since it uses less digits than its factorization.

63998472865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66319859.

The product of its digits is 156764160, while the sum is 67.

The spelling of 63998472865 in words is "sixty-three billion, nine hundred ninety-eight million, four hundred seventy-two thousand, eight hundred sixty-five".