21611301536 has 96 divisors (see below), whose sum is σ = 46980513216. Its totient is φ = 9704448000.

The previous prime is 21611301521. The next prime is 21611301563. The reversal of 21611301536 is 63510311612.

It is a junction number, because it is equal to n+sod(n) for n = 21611301499 and 21611301508.

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, 10384016 + ... + 10386096.

It is an arithmetic number, because the mean of its divisors is an integer number (489380346).

Almost surely, 2^21611301536 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 21611301536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23490256608).

21611301536 is an abundant number, since it is smaller than the sum of its proper divisors (25369211680).

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

21611301536 is a wasteful number, since it uses less digits than its factorization.

21611301536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2446 (or 2438 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 29.

The spelling of 21611301536 in words is "twenty-one billion, six hundred eleven million, three hundred one thousand, five hundred thirty-six".