21408058368 has 132 divisors (see below), whose sum is σ = 63810197568. Its totient is φ = 6905733120.

The previous prime is 21408058363. The next prime is 21408058393. The reversal of 21408058368 is 86385080412.

21408058368 is a `hidden beast` number, since 2 + 1 + 4 + 0 + 8 + 0 + 583 + 68 = 666.

It is not an unprimeable number, because it can be changed into a prime (21408058363) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 248230 + ... + 323162.

Almost surely, 2^21408058368 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 21408058368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31905098784).

21408058368 is an abundant number, since it is smaller than the sum of its proper divisors (42402139200).

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

21408058368 is a wasteful number, since it uses less digits than its factorization.

21408058368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74990 (or 74969 counting only the distinct ones).

The product of its (nonzero) digits is 368640, while the sum is 45.

The spelling of 21408058368 in words is "twenty-one billion, four hundred eight million, fifty-eight thousand, three hundred sixty-eight".