63878459905 has 32 divisors (see below), whose sum is σ = 87625123488. Its totient is φ = 44285952000.

The previous prime is 63878459903. The next prime is 63878459923. The reversal of 63878459905 is 50995487836.

It can be written as a sum of positive squares in 16 ways, for example, as 3523728321 + 60354731584 = 59361^2 + 245672^2 .

It is not a de Polignac number, because 63878459905 - 2¹ = 63878459903 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (63878459903) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 371025 + ... + 515185.

It is an arithmetic number, because the mean of its divisors is an integer number (2738285109).

Almost surely, 2^63878459905 is an apocalyptic number.

63878459905 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

63878459905 is a deficient number, since it is larger than the sum of its proper divisors (23746663583).

63878459905 is a wasteful number, since it uses less digits than its factorization.

63878459905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144597.

The product of its (nonzero) digits is 65318400, while the sum is 64.

The spelling of 63878459905 in words is "sixty-three billion, eight hundred seventy-eight million, four hundred fifty-nine thousand, nine hundred five".