63855773809 has 9 divisors (see below), whose sum is σ = 64971588793. Its totient is φ = 62758816132.

The previous prime is 63855773803. The next prime is 63855773827. The reversal of 63855773809 is 90837755836.

The square root of 63855773809 is 252697.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 63855773809 - 2²¹ = 63853676657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (63855773803) by changing a digit.

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 8 ways as a sum of consecutive naturals, for example, 14906982 + ... + 14911264.

Almost surely, 2^63855773809 is an apocalyptic number.

63855773809 is the 252697-th square number.

63855773809 is the 126349-th centered octagonal number.

It is an amenable number.

63855773809 is a deficient number, since it is larger than the sum of its proper divisors (1115814984).

63855773809 is an frugal number, since it uses more digits than its factorization.

63855773809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8684 (or 4342 counting only the distinct ones).

The product of its (nonzero) digits is 38102400, while the sum is 61.

The spelling of 63855773809 in words is "sixty-three billion, eight hundred fifty-five million, seven hundred seventy-three thousand, eight hundred nine".