21609536760 has 768 divisors, whose sum is σ = 88957440000. Its totient is φ = 4438167552.

The previous prime is 21609536759. The next prime is 21609536797. The reversal of 21609536760 is 6763590612.

21609536760 is a `hidden beast` number, since 2 + 1 + 609 + 5 + 36 + 7 + 6 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 109692982 + ... + 109693178.

It is an arithmetic number, because the mean of its divisors is an integer number (115830000).

Almost surely, 2^21609536760 is an apocalyptic number.

21609536760 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21609536760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44478720000).

21609536760 is an abundant number, since it is smaller than the sum of its proper divisors (67347903240).

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

21609536760 is a wasteful number, since it uses less digits than its factorization.

21609536760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 348 (or 341 counting only the distinct ones).

The product of its (nonzero) digits is 408240, while the sum is 45.

The spelling of 21609536760 in words is "twenty-one billion, six hundred nine million, five hundred thirty-six thousand, seven hundred sixty".