21352568508 has 36 divisors (see below), whose sum is σ = 54016090128. Its totient is φ = 7112044800.

The previous prime is 21352568507. The next prime is 21352568509. The reversal of 21352568508 is 80586525312.

21352568508 is a `hidden beast` number, since 2 + 1 + 35 + 2 + 568 + 50 + 8 = 666.

It is an interprime number because it is at equal distance from previous prime (21352568507) and next prime (21352568509).

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21352568507) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 180693 + ... + 274508.

It is an arithmetic number, because the mean of its divisors is an integer number (1500446948).

Almost surely, 2^21352568508 is an apocalyptic number.

It is an amenable number.

21352568508 is an abundant number, since it is smaller than the sum of its proper divisors (32663521620).

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

21352568508 is a wasteful number, since it uses less digits than its factorization.

21352568508 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 456514 (or 456509 counting only the distinct ones).

The product of its (nonzero) digits is 576000, while the sum is 45.

The spelling of 21352568508 in words is "twenty-one billion, three hundred fifty-two million, five hundred sixty-eight thousand, five hundred eight".