21717887148 has 36 divisors (see below), whose sum is σ = 57787362360. Its totient is φ = 6858279936.

The previous prime is 21717887143. The next prime is 21717887161. The reversal of 21717887148 is 84178871712.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (36).

It is a junction number, because it is equal to n+sod(n) for n = 21717887094 and 21717887103.

It is not an unprimeable number, because it can be changed into a prime (21717887143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15874965 + ... + 15876332.

It is an arithmetic number, because the mean of its divisors is an integer number (1605204510).

Almost surely, 2^21717887148 is an apocalyptic number.

It is an amenable number.

21717887148 is an abundant number, since it is smaller than the sum of its proper divisors (36069475212).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21717887148 is a wasteful number, since it uses less digits than its factorization.

21717887148 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31751326 (or 31751321 counting only the distinct ones).

The product of its digits is 1404928, while the sum is 54.

The spelling of 21717887148 in words is "twenty-one billion, seven hundred seventeen million, eight hundred eighty-seven thousand, one hundred forty-eight".