21513326688 has 288 divisors, whose sum is σ = 73997763840. Its totient is φ = 5791564800.

The previous prime is 21513326663. The next prime is 21513326701. The reversal of 21513326688 is 88662331512.

21513326688 is a `hidden beast` number, since 21 + 513 + 32 + 6 + 6 + 88 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a super-2 number, since 2×21513326688² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 7544463 + ... + 7547313.

It is an arithmetic number, because the mean of its divisors is an integer number (256936680).

Almost surely, 2^21513326688 is an apocalyptic number.

21513326688 is a gapful number since it is divisible by the number (28) 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 21513326688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36998881920).

21513326688 is an abundant number, since it is smaller than the sum of its proper divisors (52484437152).

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

21513326688 is a wasteful number, since it uses less digits than its factorization.

21513326688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3090 (or 3079 counting only the distinct ones).

The product of its digits is 414720, while the sum is 45.

The spelling of 21513326688 in words is "twenty-one billion, five hundred thirteen million, three hundred twenty-six thousand, six hundred eighty-eight".