63285721821 has 16 divisors (see below), whose sum is σ = 107150428800. Its totient is φ = 36163269504.

The previous prime is 63285721813. The next prime is 63285721861. The reversal of 63285721821 is 12812758236.

63285721821 is a `hidden beast` number, since 63 + 2 + 8 + 572 + 18 + 2 + 1 = 666.

It is not a de Polignac number, because 63285721821 - 2³ = 63285721813 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63285721861) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 167422356 + ... + 167422733.

It is an arithmetic number, because the mean of its divisors is an integer number (6696901800).

Almost surely, 2^63285721821 is an apocalyptic number.

It is an amenable number.

63285721821 is a deficient number, since it is larger than the sum of its proper divisors (43864706979).

63285721821 is a wasteful number, since it uses less digits than its factorization.

63285721821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 334845105 (or 334845099 counting only the distinct ones).

The product of its digits is 322560, while the sum is 45.

The spelling of 63285721821 in words is "sixty-three billion, two hundred eighty-five million, seven hundred twenty-one thousand, eight hundred twenty-one".