63813899521 has 8 divisors (see below), whose sum is σ = 65199953664. Its totient is φ = 62429025120.

The previous prime is 63813899509. The next prime is 63813899557. The reversal of 63813899521 is 12599831836.

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

It is a cyclic number.

It is not a de Polignac number, because 63813899521 - 2¹¹ = 63813897473 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (63813899581) 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 7 ways as a sum of consecutive naturals, for example, 185140 + ... + 402373.

It is an arithmetic number, because the mean of its divisors is an integer number (8149994208).

Almost surely, 2^63813899521 is an apocalyptic number.

It is an amenable number.

63813899521 is a deficient number, since it is larger than the sum of its proper divisors (1386054143).

63813899521 is a wasteful number, since it uses less digits than its factorization.

63813899521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 589871.

The product of its digits is 2799360, while the sum is 55.

The spelling of 63813899521 in words is "sixty-three billion, eight hundred thirteen million, eight hundred ninety-nine thousand, five hundred twenty-one".