21985235108 has 24 divisors (see below), whose sum is σ = 40815603864. Its totient is φ = 10326118400.

The previous prime is 21985235099. The next prime is 21985235117. The reversal of 21985235108 is 80153258912.

It is an interprime number because it is at equal distance from previous prime (21985235099) and next prime (21985235117).

It can be written as a sum of positive squares in 4 ways, for example, as 4905881764 + 17079353344 = 70042^2 + 130688^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 274853 + ... + 345708.

It is an arithmetic number, because the mean of its divisors is an integer number (1700650161).

Almost surely, 2^21985235108 is an apocalyptic number.

It is an amenable number.

21985235108 is a deficient number, since it is larger than the sum of its proper divisors (18830368756).

21985235108 is a wasteful number, since it uses less digits than its factorization.

21985235108 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 621103 (or 621101 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 44.

The spelling of 21985235108 in words is "twenty-one billion, nine hundred eighty-five million, two hundred thirty-five thousand, one hundred eight".