21353351168 has 36 divisors (see below), whose sum is σ = 42709502745. Its totient is φ = 10673369088.

The previous prime is 21353351113. The next prime is 21353351183. The reversal of 21353351168 is 86115335312.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 2 ways, for example, as 20469597184 + 883753984 = 143072^2 + 29728^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=103328.

It is a super-2 number, since 2×21353351168² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

21353351168 is a Rhonda number in base 10.

Its product of digits (64800) is a multiple of the sum of its prime factors (6480).

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 2 ways as a sum of consecutive naturals, for example, 6611378 + ... + 6614606.

Almost surely, 2^21353351168 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 21353351168

21353351168 is an abundant number, since it is smaller than the sum of its proper divisors (21356151577).

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

21353351168 is an frugal number, since it uses more digits than its factorization.

21353351168 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6480 (or 3231 counting only the distinct ones).

The product of its digits is 64800, while the sum is 38.

The spelling of 21353351168 in words is "twenty-one billion, three hundred fifty-three million, three hundred fifty-one thousand, one hundred sixty-eight".