21717068156 has 48 divisors (see below), whose sum is σ = 44793642432. Its totient is φ = 9018086400.

The previous prime is 21717068147. The next prime is 21717068167. The reversal of 21717068156 is 65186071712.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 206186 + ... + 293166.

It is an arithmetic number, because the mean of its divisors is an integer number (933200884).

Almost surely, 2^21717068156 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21717068156, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22396821216).

21717068156 is an abundant number, since it is smaller than the sum of its proper divisors (23076574276).

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

21717068156 is a wasteful number, since it uses less digits than its factorization.

21717068156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87270 (or 87268 counting only the distinct ones).

The product of its (nonzero) digits is 141120, while the sum is 44.

The spelling of 21717068156 in words is "twenty-one billion, seven hundred seventeen million, sixty-eight thousand, one hundred fifty-six".