21403444608 has 288 divisors, whose sum is σ = 77160152160. Its totient is φ = 5644670976.

The previous prime is 21403444547. The next prime is 21403444631. The reversal of 21403444608 is 80644430412.

21403444608 is a `hidden beast` number, since 2 + 1 + 4 + 0 + 3 + 4 + 44 + 608 = 666.

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

It is a super-3 number, since 3×21403444608³ (a number of 32 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 719241 + ... + 748407.

It is an arithmetic number, because the mean of its divisors is an integer number (267917195).

Almost surely, 2^21403444608 is an apocalyptic number.

21403444608 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 21403444608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38580076080).

21403444608 is an abundant number, since it is smaller than the sum of its proper divisors (55756707552).

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

21403444608 is a wasteful number, since it uses less digits than its factorization.

21403444608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29214 (or 29192 counting only the distinct ones).

The product of its (nonzero) digits is 73728, while the sum is 36.

The spelling of 21403444608 in words is "twenty-one billion, four hundred three million, four hundred forty-four thousand, six hundred eight".