21536327736 has 512 divisors, whose sum is σ = 80372736000. Its totient is φ = 5171558400.

The previous prime is 21536327663. The next prime is 21536327741. The reversal of 21536327736 is 63772363512.

21536327736 is a `hidden beast` number, since 2 + 1 + 5 + 3 + 632 + 7 + 7 + 3 + 6 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 21536327691 and 21536327700.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 16681251 + ... + 16682541.

It is an arithmetic number, because the mean of its divisors is an integer number (156978000).

Almost surely, 2^21536327736 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 21536327736, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40186368000).

21536327736 is an abundant number, since it is smaller than the sum of its proper divisors (58836408264).

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

21536327736 is a wasteful number, since it uses less digits than its factorization.

21536327736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1400 (or 1390 counting only the distinct ones).

The product of its digits is 952560, while the sum is 45.

The spelling of 21536327736 in words is "twenty-one billion, five hundred thirty-six million, three hundred twenty-seven thousand, seven hundred thirty-six".