21711689136 has 120 divisors (see below), whose sum is σ = 61985139840. Its totient is φ = 7091954688.

The previous prime is 21711689117. The next prime is 21711689149. The reversal of 21711689136 is 63198611712.

It is a junction number, because it is equal to n+sod(n) for n = 21711689091 and 21711689100.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9836545 + ... + 9838751.

It is an arithmetic number, because the mean of its divisors is an integer number (516542832).

Almost surely, 2^21711689136 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 21711689136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30992569920).

21711689136 is an abundant number, since it is smaller than the sum of its proper divisors (40273450704).

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

21711689136 is a wasteful number, since it uses less digits than its factorization.

21711689136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3563 (or 3554 counting only the distinct ones).

The product of its digits is 108864, while the sum is 45.

The spelling of 21711689136 in words is "twenty-one billion, seven hundred eleven million, six hundred eighty-nine thousand, one hundred thirty-six".