21508748352 has 756 divisors, whose sum is σ = 81113081868. Its totient is φ = 5399654400.

The previous prime is 21508748269. The next prime is 21508748377. The reversal of 21508748352 is 25384780512.

21508748352 is a `hidden beast` number, since 21 + 508 + 74 + 8 + 3 + 52 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1735888896 + 19772859456 = 41664^2 + 140616^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21508748298 and 21508748307.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 352602402 + ... + 352602462.

Almost surely, 2^21508748352 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 21508748352, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40556540934).

21508748352 is an abundant number, since it is smaller than the sum of its proper divisors (59604333516).

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

21508748352 is a wasteful number, since it uses less digits than its factorization.

21508748352 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168 (or 117 counting only the distinct ones).

The product of its (nonzero) digits is 537600, while the sum is 45.

The spelling of 21508748352 in words is "twenty-one billion, five hundred eight million, seven hundred forty-eight thousand, three hundred fifty-two".